I've been interested in cults since my late teens when I went to a talk by some people who had been Moonies. I realized I kind of fit the profile of somebody who could be vulnerable to something like that.
What I think you'll find in common is that a lot of people who weren't born into Scientology aren't what you would call book smart. In many instances they have experienced some level of success in the entertainment field (I'm not talking about regular citizens here, but the showbiz ones) and they probably have some sort of inferiority complex about their lack of education. What something like Scientology does is offer them something they can become experts in, (as long as they pay the fees), that tells them they will eventually be able to control matter and space and time, and it gives them insider vocabulary that is essentially meaningless and non-transferrable in the real world. However, they move up the bridge, ie ascend the achievement ladder by memorizing stuff that only exists in that special world.
And of course, not everybody who isn't book smart chooses Scientology. Madonna is a classic example of somebody with a native intelligence who basically fell into the kabbalah cult. These folks don't have the critical thinking skills they might have developed academically if fame hadn't come calling. So, instead, they fill their minds up with a different struture, to help them make sense of the world.
Is what I wrote too vague?
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