Ranked Choice has some fundamental flaws that make it a very poor replacement for the broken system that is First Past the Post.
I’ll list the flaws in no particular order, but each one is enough of an issue that RCV should never be used in a real election.
First is election security. All ballots cast in an RCV election must be tabulated in a central location. This means that a malicious actor could introduce extra ballots, and those ballots would likely be counted.
Then there was Burlington in 2009. The Condorcet winner was eliminated in the second round. For anyone who doesn’t know, the Condorcet winner is also called the Pairwise Winner, in that if you were to take all candidates and pair them off, the Condorcet winner should win every matchup.
This leads to a discussion of Monotonicity. RCV is one of the only voting systems ever designed that fails monotonicity.
An election method is monotonic if it is neither possible to prevent the election of a candidate by ranking them higher on some of the ballots, nor possible to elect an otherwise unelected candidate by ranking them lower on some of the ballots (while nothing else is altered on any ballot).
I’ll spell this out a bit because it’s fucking amazing, in RCV it’s possible to make a candidate lose by ranking them higher on a ballot.
The next issue is Ballot exhaustion. Say you only get 5 choices on a ballot that has 6 or 7 candidates. You rank your 5 and the first round sees your second choice eliminated. Then your third, then your fourth, then your fifth, and finally your first.
Your ballot is thrown out and is not counted at all. Now, RCV rules say that the winner must have 50% of the vote, but that’s 50% of the final vote. Your ballot doesn’t count anymore.
There are studies that say that ballot exhaustion rates can be up to 18% of the initial votes cast. So the final winner can be liked by just 41.1% of the initial voters.
There’s also the issue of those eliminated candidates. Say your first choice was eliminated early. Then your second might have had that extra vote to stay in, and eventually win. But no, your ballot was gutted down the middle before being thrown out.
There are still more issues with RCV, but this is already an essay, so I’ll leave it at that.
There is a better option. A few actually, but the one I currently prefer is called STAR. It’s simple and it’s actually good at all the things RCV claims to be good at.
I don’t doubt that RCV has flaws. But we know that FPTP has flaws. So the question then becomes, Is RCV or FPTP the better voting system? If RCV is a better voting system than it should be pushed for and supported because of that fact.
For example, If someone is so obsessed with making sure your comment is completely accurate and factual that they end up deleting and never posting the comment, then that comment will not help anyone. Or for another example, I shouldn’t wear a mask because it won’t fully protect me or others from coronavirus. Doing something even is if it is an imperfect improvement is better than doing nothing.
I believe an RCV system is better than FPTP and therefore support it. I also would support STAR for the same reason.
I am usually the one making the “perfect is the enemy of the good” argument, and you make excellent points in this case.
I will add some nuance to the enemy of the good argument, in that:
Doing something even is if it is an imperfect improvement is better than doing nothing.
does not factor in the potential harm of the imperfect thing. It’s a no-brainer with masks, because there is none. But it is worth taking a close look at whether the problems with IRV are less harmful than FPTP, and, more importantly, if implementing IRV prevents the institution of a better system (like potentially STAR). If there’s one opportunity to switch our voting method, and we go with a less effective one, would that prevent changing it again to an even better system?
I’ll give you an example: I’m not sure if this is still going on, but the Salvation Army was found to be rejecting LGBTQ people from shelters and support. Now, you can say “they still help a lot of people, so not supporting them harms those who do get support from the SA.” The perfect being the enemy of the good. But establishing a monolith of an organization like the Salvation Army as the go-to charity for the poor and/or homeless cuts the legs out from any charity that may support everyone, not just straight cis-gendered people.
In the same way, if IRV gets popular and cements itself as the alternative to FPTP, it could be that it prevents other forms like STAR from even being considered. It’s worth considering, particularly as FPTP alternative implementation is in its infancy, what alternatives are available.
Why not say you would support IRV or better, especially multi member districts and proportional results? Why put so much effort in trying to push against the facts about IRV? Frankly if IRV gets put in place and people are not aware of its strange chaotic behavior it will get repealed, which isn’t my conjecture its reality.
Why not say you would support IRV or better, especially multi member districts and proportional results?
I do and I did. See my last paragraph. Sure, I used different words than you did but I was trying to imply the same thing.
Why put so much effort in trying to push against the facts about IRV?
I did no such thing. Don’t strawman me by putting works in my mouth.
Frankly if IRV gets put in place and people are not aware of its strange chaotic behavior it will get repealed, which isn’t my conjecture its reality.
That is your conjecture, unless you give an example of that happening. I will grant you that it is conceivable that such a circumstance happen, but that doesn’t make it not a conjecture.
I guess my point is that it isn’t really helpful for us to argue about different voting systems when we largely agree that we need to move away from a FPTP system. It just serves to promote division. Unless we are actually doing the groundwork of pushing for different voting systems, arguing about the details of the different systems is just not needed.
Both Canada and the US had and repealed irv in multiple jurisdictions.
Your whole post is to tell everyone to chill on the criticism of IRV, its not a strawman its your actions.
I guess my point is that it isn’t really helpful for us to argue about different voting systems when we largely agree that we need to move away from a FPTP system. It just serves to promote division. Unless we are actually doing the groundwork of pushing for different voting systems, arguing about the details of the different systems is just not needed.
Right there, you just did it.
IRV is not a good enough solution to promote, imo. I don’t agree with you and you are actively hurting the adoption of a proportional system, the only election system that results in a meaningful number of parties. STV is fine, IRV is not.
Is there any voting system that doesn’t have flaws? I mean these are serious concerns, but what can we do to fix FPTP and have an electoral system that will allow us to get the people in that aren’t literal greedy psychopaths?
No, Arrow’s impossibility theorem says that all voting systems have flaws, if you agree with the things it defines as flaws.
The most doubtful of the flaws is the “Independence of irrelevant alternatives” criterion, which says that: if you run two elections in which voters change rank candidates A and B the same with respect to one another, the elections will both rank those candidates the same.
The problem with this is that if voters change their ranking for some other candidate C it can end up affecting the outcome for candidates A and B, when arguably it shouldn’t. But this makes less sense if you realise that aggregating voter preferences can end up implying that candidate A is better than B who is better than C… who is better than A. This setup makes it impossible to maintain the principle.
Arrow’s Theorem only really applies to Ordinal voting systems like RCV and Plurality.
Cardinal systems like STAR, Score, and Approval are all immune, but have other quirks, but seem to better represent the desires of an aggregate population.
I think people are wary of systems where you assign a relative score for good reason. Is my favourite party twice as good as the major party that kind represents my views, or is it only a little bit better? It’s kind of impossible to make those judgements well IMO. In STAR in particular, what you actually want to do is rank your preferences, but if there are many candidates are forced not to because you only have five scores available.
Also you seem to have replied about STAR to just about every comment in the thread… maybe chill? lol…
Mate, I know plenty about voting systems. You don’t need to rattle them off.
As to “forcing you to rank candidates” that’s hogwash.
In STAR, if you have four candidates and you feel like two are pretty similar, you might give them both a three. But if they then make it to the runoff, you’ve no longer expressed a preference between them. Do you prioritise expressing your preferences in the first round (where you might not want to help either of them win against your favourite whom you awarded 5) or in the runoff?
Forcing people to use a bad system because you think they aren’t smart enough to rate someone on a scale of 0-5 is kind of mind-boggling.
Who is “forcing” people to use a “bad” system? Which bad system? Do you think that, because I don’t like STAR which you’ve spammed the entire thread with, I must be in love with FPTP? Let’s take a deep breath here…
Sounds like FUD for any voting system. Security comes from other aspects. Lots of elections use Instant Runoff Voting and STV which has similar properties, without security problems.
spoiler effect, monotonicity issues
Listing these issues is a bit pointless given impossibility theorems. No electoral system can be both Condorcet compatible (always elects the candidate who beats all other candidates in a head-to-head, if such a candidate exists) without also potentially rewarding abstentions (i.e. there are situations where changing from not voting to entering a vote which prefers candidate A to candidate B can cause candidate B to win instead of A). STAR voting satisfies neither principle. IRV satisfies the property that if you switch from ranking A > B > C to A > C > B this can never cause A to lose - STAR voting does not (this is what I outlined above, or part of it).
All voting systems are compromises. But this last issue gets to the real heart of it: STAR voting has this issue precisely because it, as a scoring system, is explicitly saying “one hundred people each assigning this candidate a 1 indicates they should win over a candidate who got 49 2s and no other votes”. Ranking methods are denying the ability to trade off many weak preferences against fewer strong preferences and go only by rankings. Each leads to different issues; you need to go more into those rather than just focus on a list of mathematical properties.
IRV is significantly better than FPTP because the spoiler effect is much less, possibly below the threshold where most voters would actually attempt to vote tactically. STV is significantly better than IRV because it is much more proportional. MMP is even better because it’s simpler and arguably has better local ties between representatives and electorates. These are the real issues - mathematical properties are interesting but not the final word.
It has far fewer flaws than any other system I’ve seen.
For the voter. It’s dead simple. Rate each candidate on a scale of 0-5. Multiple candidates can be rated the same.
To count, you just add up the ratings for each candidate. Take the top two and then look at each ballot. If A is rated higher than B on that ballot, then the vote goes to A.
That’s it.
The fact that each candidate’s vote doesn’t detract from any other vote means there’s literally no way for a spoiler candidate to exist. They’re just another option on the ballot.
The automatic runoff in the end encourages voters to rate on a scale and not just bullet vote. But even if they bullet vote, the system is still spoiler free.
You had me until STAR. STAR is just approval voting with extra steps, since min/maxing your ballot is the easiest way to game it, and, perhaps I’m missing something, but I have no idea how a runoff is actually supposed to stop it. Seems like a waste to give a middling score to someone I’d want in the 2nd place spot. I’m open to alternatives to RCV, but I don’t see STAR as an improvement.
I actually think a major part of the problem in US politics is that the balance of power is effectively upside down compared to most modern democracies.
Here in Ireland for example, we have three levels just like you: the Dáil is like the House of Representatives, the Seanad is the senate, and we both have presidents. However the head of government here is the leader of the largest party in the Dáil, and the other two are really figureheads. It means that other parties are way more involved in government and lessens the tendencies for a single figurehead to run rampant, changing stuff to suit himself every 4-8 years.
Ireland also uses PR, but we’ve actually gotten quite good at the vote counts, and we probably don’t have the same threat of bad actors in some other countries.
It’s the same in the UK - parliament is the actual government, while the House of Lords and the king are at this stage vestigial. But they use fptp, which is making it difficult to remove a minority government for the last dozen years or so.
I wouldn’t say that it is worse than what we have. It’s different from plurality voting but fixes a few things. The biggest problem is that it isn’t all of the things it claims to be, and you still need to be strategic with your vote.
Ranked Choice is literally a series of plurality elections on the same ballot.
So it’s exactly as bad as plurality, but worse because it’s also confusing to count, and has inherent security issues from needing to be counted in a centralized location.
You cannot fix the problems of plurality by iterating plurality.
Ranked Choice is very attractive to people who don’t realize that it marginalizes third parties even more than a simple plurality election.
Here’s the thing, if your third party is small and has no chance of actually winning, then Ranked Choice will keep them from ruining the election for the two major parties.
The thing is, the second that third party becomes even slightly more popular than the major party closest to them on the spectrum, the candidate furthest from them on the spectrum wins.
See, if A B and C are in an election where A has 40%, B has 29% and C (the new third party) has 31%. When B is eliminated, it doesn’t matter that Every single C voter put B as their second, because B is gone.
All it takes is for a third of B voters (10% of the total) to put A first for A to win. This is the absolute worst outcome for C voters, and if just a handful had voted dishonestly for B first, B would have won.
This is a high bar to hit when there are only three candidates, but when there are five? Well, the numbers get worse. More than that, and RCV just starts breaking in new and interesting ways.
Ranked Choice is a broken system pretending to be a viable one. In my top comment, I pointed to a bunch of real world examples of it breaking down in ways that no other voting system is subject to.
It’s not exactly as bad, because it does present opportunities for breaking the deadlocked two party system. It does not go far enough to improve on plurality, and I agree that the logistical issues make implementation a fools errand. The spoiler effect is still an edge case that has much less effect than a simple plurality vote between 3 candidates.
I’m not advocating for ranked choice. I’m on board with STAR voting, and I also like almost any other voting system better than both plurality and ranked choice.
It does not, in fact, break the two party system. Full stop.
RCV still has the spoiler effect, and is in fact worse for third parties.
If the third party is small, then RCV will sideline them harder than FPtP, if they get big enough to matter, then RCV will break and the worst candidate will be elected.
See any RCV election with three or more viable candidates, but particularly Burlington 2009.
So RCV fails to do the one thing that people say it’s good for. It does not break the two party system. Something we’ve known for a long time, seeming as how it’s used in one category of Australian elections, and that particular category is dominated by two parties. (other areas of Australian politics use proportional elections, but one section of their government is single winner RCV)
Ranked Choice has some fundamental flaws that make it a very poor replacement for the broken system that is First Past the Post.
I’ll list the flaws in no particular order, but each one is enough of an issue that RCV should never be used in a real election.
First is election security. All ballots cast in an RCV election must be tabulated in a central location. This means that a malicious actor could introduce extra ballots, and those ballots would likely be counted.
This has happened before. There was no malice in the 2021 NYC Mayoral race, but there were extra ballots that were counted.
The next issue is one of counting procedure. It’s confusing as hell. I know it is because in Alameda County, the wrong candidate was actually sworn in before anyone noticed the issue.
Then there was Burlington in 2009. The Condorcet winner was eliminated in the second round. For anyone who doesn’t know, the Condorcet winner is also called the Pairwise Winner, in that if you were to take all candidates and pair them off, the Condorcet winner should win every matchup.
This leads to a discussion of Monotonicity. RCV is one of the only voting systems ever designed that fails monotonicity.
I’ll spell this out a bit because it’s fucking amazing, in RCV it’s possible to make a candidate lose by ranking them higher on a ballot.
Then there are issues of ballot spoilage (incorrectly filled ballots) at rates about twice that of simple Plurality. These rates tend to be higher in low income or marginalized areas.
The next issue is Ballot exhaustion. Say you only get 5 choices on a ballot that has 6 or 7 candidates. You rank your 5 and the first round sees your second choice eliminated. Then your third, then your fourth, then your fifth, and finally your first.
Your ballot is thrown out and is not counted at all. Now, RCV rules say that the winner must have 50% of the vote, but that’s 50% of the final vote. Your ballot doesn’t count anymore.
There are studies that say that ballot exhaustion rates can be up to 18% of the initial votes cast. So the final winner can be liked by just 41.1% of the initial voters.
There’s also the issue of those eliminated candidates. Say your first choice was eliminated early. Then your second might have had that extra vote to stay in, and eventually win. But no, your ballot was gutted down the middle before being thrown out.
There are still more issues with RCV, but this is already an essay, so I’ll leave it at that.
There is a better option. A few actually, but the one I currently prefer is called STAR. It’s simple and it’s actually good at all the things RCV claims to be good at.
I don’t doubt that RCV has flaws. But we know that FPTP has flaws. So the question then becomes, Is RCV or FPTP the better voting system? If RCV is a better voting system than it should be pushed for and supported because of that fact.
Perfect is the enemy of good. It is relevant in life and in politics.
For example, If someone is so obsessed with making sure your comment is completely accurate and factual that they end up deleting and never posting the comment, then that comment will not help anyone. Or for another example, I shouldn’t wear a mask because it won’t fully protect me or others from coronavirus. Doing something even is if it is an imperfect improvement is better than doing nothing.
I believe an RCV system is better than FPTP and therefore support it. I also would support STAR for the same reason.
I am usually the one making the “perfect is the enemy of the good” argument, and you make excellent points in this case.
I will add some nuance to the enemy of the good argument, in that:
does not factor in the potential harm of the imperfect thing. It’s a no-brainer with masks, because there is none. But it is worth taking a close look at whether the problems with IRV are less harmful than FPTP, and, more importantly, if implementing IRV prevents the institution of a better system (like potentially STAR). If there’s one opportunity to switch our voting method, and we go with a less effective one, would that prevent changing it again to an even better system?
I’ll give you an example: I’m not sure if this is still going on, but the Salvation Army was found to be rejecting LGBTQ people from shelters and support. Now, you can say “they still help a lot of people, so not supporting them harms those who do get support from the SA.” The perfect being the enemy of the good. But establishing a monolith of an organization like the Salvation Army as the go-to charity for the poor and/or homeless cuts the legs out from any charity that may support everyone, not just straight cis-gendered people.
In the same way, if IRV gets popular and cements itself as the alternative to FPTP, it could be that it prevents other forms like STAR from even being considered. It’s worth considering, particularly as FPTP alternative implementation is in its infancy, what alternatives are available.
Why not say you would support IRV or better, especially multi member districts and proportional results? Why put so much effort in trying to push against the facts about IRV? Frankly if IRV gets put in place and people are not aware of its strange chaotic behavior it will get repealed, which isn’t my conjecture its reality.
I do and I did. See my last paragraph. Sure, I used different words than you did but I was trying to imply the same thing.
I did no such thing. Don’t strawman me by putting works in my mouth.
That is your conjecture, unless you give an example of that happening. I will grant you that it is conceivable that such a circumstance happen, but that doesn’t make it not a conjecture.
I guess my point is that it isn’t really helpful for us to argue about different voting systems when we largely agree that we need to move away from a FPTP system. It just serves to promote division. Unless we are actually doing the groundwork of pushing for different voting systems, arguing about the details of the different systems is just not needed.
https://en.wikipedia.org/wiki/History_and_use_of_instant-runoff_voting?wprov=sfla1
Both Canada and the US had and repealed irv in multiple jurisdictions.
Your whole post is to tell everyone to chill on the criticism of IRV, its not a strawman its your actions.
Right there, you just did it.
IRV is not a good enough solution to promote, imo. I don’t agree with you and you are actively hurting the adoption of a proportional system, the only election system that results in a meaningful number of parties. STV is fine, IRV is not.
Kinda low to attack me and not the argument. That is otherwise known as an ad hominem.
It’s pretty clear your treating this as a pissing match and I have no interest in that.
Is there any voting system that doesn’t have flaws? I mean these are serious concerns, but what can we do to fix FPTP and have an electoral system that will allow us to get the people in that aren’t literal greedy psychopaths?
No, Arrow’s impossibility theorem says that all voting systems have flaws, if you agree with the things it defines as flaws.
The most doubtful of the flaws is the “Independence of irrelevant alternatives” criterion, which says that: if you run two elections in which voters change rank candidates A and B the same with respect to one another, the elections will both rank those candidates the same.
The problem with this is that if voters change their ranking for some other candidate C it can end up affecting the outcome for candidates A and B, when arguably it shouldn’t. But this makes less sense if you realise that aggregating voter preferences can end up implying that candidate A is better than B who is better than C… who is better than A. This setup makes it impossible to maintain the principle.
Arrow’s Theorem only really applies to Ordinal voting systems like RCV and Plurality.
Cardinal systems like STAR, Score, and Approval are all immune, but have other quirks, but seem to better represent the desires of an aggregate population.
I think people are wary of systems where you assign a relative score for good reason. Is my favourite party twice as good as the major party that kind represents my views, or is it only a little bit better? It’s kind of impossible to make those judgements well IMO. In STAR in particular, what you actually want to do is rank your preferences, but if there are many candidates are forced not to because you only have five scores available.
Also you seem to have replied about STAR to just about every comment in the thread… maybe chill? lol…
STAR is great, but I can also talk about Approval. That one is dead simple.
The ballot is the same as a FPtP ballot except instead of it saying “mark one” it says something like “mark one or more”.
Approval says vote for as many people as you want, and if any of them win, you’ll be happy. Or not. I’m not the boss of you.
As to “forcing you to rank candidates” that’s hogwash.
Forcing people to use a bad system because you think they aren’t smart enough to rate someone on a scale of 0-5 is kind of mind-boggling.
Mate, I know plenty about voting systems. You don’t need to rattle them off.
In STAR, if you have four candidates and you feel like two are pretty similar, you might give them both a three. But if they then make it to the runoff, you’ve no longer expressed a preference between them. Do you prioritise expressing your preferences in the first round (where you might not want to help either of them win against your favourite whom you awarded 5) or in the runoff?
Who is “forcing” people to use a “bad” system? Which bad system? Do you think that, because I don’t like STAR which you’ve spammed the entire thread with, I must be in love with FPTP? Let’s take a deep breath here…
RCV is literally a bad system. See my other comments about it.
But it has things like the spoiler effect, monotonicity issues, security issues, and more.
It’s a bad system, that’s already failed multiple times in real world election, and people are still pushing for it to have wider implementation.
Sounds like FUD for any voting system. Security comes from other aspects. Lots of elections use Instant Runoff Voting and STV which has similar properties, without security problems.
Listing these issues is a bit pointless given impossibility theorems. No electoral system can be both Condorcet compatible (always elects the candidate who beats all other candidates in a head-to-head, if such a candidate exists) without also potentially rewarding abstentions (i.e. there are situations where changing from not voting to entering a vote which prefers candidate A to candidate B can cause candidate B to win instead of A). STAR voting satisfies neither principle. IRV satisfies the property that if you switch from ranking A > B > C to A > C > B this can never cause A to lose - STAR voting does not (this is what I outlined above, or part of it).
All voting systems are compromises. But this last issue gets to the real heart of it: STAR voting has this issue precisely because it, as a scoring system, is explicitly saying “one hundred people each assigning this candidate a 1 indicates they should win over a candidate who got 49 2s and no other votes”. Ranking methods are denying the ability to trade off many weak preferences against fewer strong preferences and go only by rankings. Each leads to different issues; you need to go more into those rather than just focus on a list of mathematical properties.
IRV is significantly better than FPTP because the spoiler effect is much less, possibly below the threshold where most voters would actually attempt to vote tactically. STV is significantly better than IRV because it is much more proportional. MMP is even better because it’s simpler and arguably has better local ties between representatives and electorates. These are the real issues - mathematical properties are interesting but not the final word.
I like STAR.
It has far fewer flaws than any other system I’ve seen.
For the voter. It’s dead simple. Rate each candidate on a scale of 0-5. Multiple candidates can be rated the same.
To count, you just add up the ratings for each candidate. Take the top two and then look at each ballot. If A is rated higher than B on that ballot, then the vote goes to A.
That’s it.
The fact that each candidate’s vote doesn’t detract from any other vote means there’s literally no way for a spoiler candidate to exist. They’re just another option on the ballot.
The automatic runoff in the end encourages voters to rate on a scale and not just bullet vote. But even if they bullet vote, the system is still spoiler free.
You had me until STAR. STAR is just approval voting with extra steps, since min/maxing your ballot is the easiest way to game it, and, perhaps I’m missing something, but I have no idea how a runoff is actually supposed to stop it. Seems like a waste to give a middling score to someone I’d want in the 2nd place spot. I’m open to alternatives to RCV, but I don’t see STAR as an improvement.
I actually think a major part of the problem in US politics is that the balance of power is effectively upside down compared to most modern democracies.
Here in Ireland for example, we have three levels just like you: the Dáil is like the House of Representatives, the Seanad is the senate, and we both have presidents. However the head of government here is the leader of the largest party in the Dáil, and the other two are really figureheads. It means that other parties are way more involved in government and lessens the tendencies for a single figurehead to run rampant, changing stuff to suit himself every 4-8 years.
Ireland also uses PR, but we’ve actually gotten quite good at the vote counts, and we probably don’t have the same threat of bad actors in some other countries.
It’s the same in the UK - parliament is the actual government, while the House of Lords and the king are at this stage vestigial. But they use fptp, which is making it difficult to remove a minority government for the last dozen years or so.
Ah wall of text is there nothing that can make me ignore an argument faster ?
If reading makes you ignore intelligent arguments, that says more about your intelligence than the argument.
I’ll make it simple. RCV is broken and bad, and in some ways worse than the broken and bad system we already have.
There are better systems that are not broken. My current favorite is STAR.
I wouldn’t say that it is worse than what we have. It’s different from plurality voting but fixes a few things. The biggest problem is that it isn’t all of the things it claims to be, and you still need to be strategic with your vote.
Ranked Choice is literally a series of plurality elections on the same ballot.
So it’s exactly as bad as plurality, but worse because it’s also confusing to count, and has inherent security issues from needing to be counted in a centralized location.
You cannot fix the problems of plurality by iterating plurality.
If say, your goal is elevating third parties, ranked choice is very attractive, as 3p voters can do so without “throwing away” their vote.
Not refuting your concerns, just saying folks are drawn to systems for particular reasons.
Ranked Choice is very attractive to people who don’t realize that it marginalizes third parties even more than a simple plurality election.
Here’s the thing, if your third party is small and has no chance of actually winning, then Ranked Choice will keep them from ruining the election for the two major parties.
The thing is, the second that third party becomes even slightly more popular than the major party closest to them on the spectrum, the candidate furthest from them on the spectrum wins.
See, if A B and C are in an election where A has 40%, B has 29% and C (the new third party) has 31%. When B is eliminated, it doesn’t matter that Every single C voter put B as their second, because B is gone.
All it takes is for a third of B voters (10% of the total) to put A first for A to win. This is the absolute worst outcome for C voters, and if just a handful had voted dishonestly for B first, B would have won.
This is a high bar to hit when there are only three candidates, but when there are five? Well, the numbers get worse. More than that, and RCV just starts breaking in new and interesting ways.
Ranked Choice is a broken system pretending to be a viable one. In my top comment, I pointed to a bunch of real world examples of it breaking down in ways that no other voting system is subject to.
It’s not exactly as bad, because it does present opportunities for breaking the deadlocked two party system. It does not go far enough to improve on plurality, and I agree that the logistical issues make implementation a fools errand. The spoiler effect is still an edge case that has much less effect than a simple plurality vote between 3 candidates.
I’m not advocating for ranked choice. I’m on board with STAR voting, and I also like almost any other voting system better than both plurality and ranked choice.
It does not, in fact, break the two party system. Full stop.
RCV still has the spoiler effect, and is in fact worse for third parties.
If the third party is small, then RCV will sideline them harder than FPtP, if they get big enough to matter, then RCV will break and the worst candidate will be elected.
See any RCV election with three or more viable candidates, but particularly Burlington 2009.
So RCV fails to do the one thing that people say it’s good for. It does not break the two party system. Something we’ve known for a long time, seeming as how it’s used in one category of Australian elections, and that particular category is dominated by two parties. (other areas of Australian politics use proportional elections, but one section of their government is single winner RCV)