For me it was when I learned that GB makes their decisions by 2/3 majority vote, NOT by direction of holy spirit.
What was your "Aha!" moment?
My first doubts arised when I noticed that the new testament uses the name "Jehovah" a very few times. Then I read an autobiography of a former Budapest bethel member who actually was in the NWT hungarian translation team.
I couldn't define an aha moment though.
For me, it was when I agreed to go to a JC meeting. The way I was treated, the way they twisted things to make be look bad when I had done nothing except get away made me angry. I did not express my rage, and played it cool. Somehow they got the impression that I wanted to come back. Maybe it was because I didn't yell or show my rage.
I realized how lucky I was to live in a time and place where it was illegal to burn me at the stake because I got the impression that they would have loved to do just that!
I left that meeting a free woman! Immediately afterward, I went and found a friend (another ex-JW) to celebrate! This was in 1979.
My Aha moment occurred months after my mom died.
I realized that (for years) I had hoped my mom would die before Armaggedon-- so that she could live in the new system.
Edited to add:
Thereafter the "mentally diseased" mention in a 2011 WT article.
For me I always had my doubts. It was until reading Crisis of Conscience that I understood why.
Once 607bce was totally and easily debunked then the whole lot stood on nothing, no 607, no 1914 etc etc.
Mum - I can relate to that. My JC was was made up of 3 what I considered my friends. They treated me respectfully, but what really got me was how cold and business-like they appeared, they didn't show any concerns for me, just read a few scriptures and were done with me. By the way - they wouldn't burn you at stake, the preferred biblical method is stoning ;)
Rippy - truly, "the truth" is making people think and behave in unnatural way. I was thinking the same about my Dad, thankfully he is still alive and well.
pronomono - I, on the other hand, really believed it, just the last 5 years felt weird (dissonance setting in). After I was Dfed I went on the Internet and learnd why.
I have posted many times before my "Aha !" moment, but will do so again in the hope it will help someone perhaps.
It was when reading the Book of Daniel, it suddenly struck me that 1914 simply was not in there, and any method to "Extend" the prophecy about the 7 times was without warrant. The fulfillment of the prophecy was right there in the same Chapter as the prophecy was given. If God had wanted us to interpret it for another time in history He would have given us a clue that we should do that.
Looking back over my life, I was born-in, I realise that I had rejected so much of the rubbish even before this final "Aha!".
I often describe it as me having a religion within a religion, or perhaps more accurately, me retaining some faith in the Bible and God whilst realising the religion I was in was like any other, not from god.
But once 1914 is gone, the GB and WT has no authority to claim anything about itself, or to interpret Scripture.
The whole House of Cards that is JW/WT teaching fell down. I left for good not long after.
The second best most wonderful move I have ever made in my life, the first was marrying Mrs Phizzy, bless her.