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.
Randomly learning that Jerusalem was destroyed in 587 and not 607 was all it took for me. I always believed JWs were “the truth” and when I realized that wasn’t true I gave up on it.