First of all, because it completely invalidates, and nearly calls a person a liar. It is an assumption, and a person telling another person what their true motivation is. Nobody here is qualified to do such a thing.
I see your point and that's fair. It was just my inner voice talking. That's why I said " I'll give them the benefit of the doubt, however. I just see a larger ratio of JWs and Mormons becoming atheists compared to other ex members." It's not an accusation or assumption. More of a pondering over "Why?". And I DO realize that everyone has a different story and reason for coming to their conclusions. I used to go around saying that exJWs tend to throw the baby out with the bathwater. I see why that's not accurate in many cases. But I really do personally feel that it's accurate in SOME cases. My pondering is mostly about why it seems that exJW's become atheists far more than people that leave other religious organizations.
I think cofty's point was the best so far. Because of having to struggle so much with belief in the JW organization and question all of their beliefs, they also include EVERYTHING in that questioning process, including God. I'm no different. I just came to a different conclusion than some others.