Basically, for me it was a combination of things. Feeling that life was unfair to me even though I was a perfect JW was the beginning. The JW way of life is strict beyond belief and I had felt embarassed inside because of practicing it. The next part was the actual information. I watched a lot of Propaganda Techniques’ (a YouTube channel about the Watchtower) channel and I don’t know if I would have stayed out of the tower without that information.
Long story short: Same as you, I was as perfect as possible but always overlooked. I moved around a lot, thinking the problem was just the people in my immediate area. It became clear the problem was everywhere. When I started divorce proceedings, I got treated terribly. Called Bethel for help and all they said was “just listen to the elders, they never steer anyone wrong.” My mom and I looked at each other and realized it was all bullshit. We quit that day. It took me 3 years months before I started researching and found out all the things wrong with JWs.
I was on YouTube a lot. Some of the channels I watched were taken down though like CS the Apostate. JW Fairytale was a popular one at the time but I wasn’t into it as much as I am now.
I think reading the new testament on its own without WT literature is enough research to know the WT is deceiving.