The flood story, Balaam striking up a casual conversation with his donkey, and the paradox-problem of praying for others made me decide that the Bible couldn't really be a "Holy Book", so JW's couldn't really have "the truth" since there was no truth to be had. I assumed (naively) that they still had the Bible right, but the Bible itself was wrong.
Then I met you kind folks. 
Now I see that you can pretty much prove and disprove anything you like from the Bible. I've always been pretty gullible, and I guess when they disproved the other religion's doctrines, and proved their own, coupled with giving me reasons to believe the Bible, I bought it. It never occurred to me (stupidly) to see if any other religion could do the same thing. Terry has mentioned that he's ashamed of himself for allowing himself to be misled this way, for blindly buying things without proof that have such a high price. Once I saw JW's for what they really are, I was ashamed, and angry.
And for the record, the made-up rules like birthdays, holidays, blood and fractions, and the 607 thing were killers for me. Oh, and the "we don't know what we're talking about so we're going to change our minds every year or two and call it 'New Light'" policy seems ludicrous now, though I bought it happily as a dub. I was never too impressed with the UN scandal, though it's interesting. I think if I'd been a dub and been told about the UN thing, I wouldn't have considered it a big deal.
Dave