(Atheism) ...usually is a choice.
I doubt it.
Belief is no more a matter of choice than is sexual orientation. What you believe is what you percieve to be true. This is not a choice; it's a perception. We can't "choose" to believe something. We can only choose to pretend to believe... an action which describes Christian faith far better than it does atheism. It is the Christians who have not "examined the evidence and arguments" and who, when presented with evidence damaging to the notion of a divinely inspired bible and an all-powerful, all-wise God, get angry, threaten fiery retribution, clutch at straws to save their fragile belief system.
I think that there are several probable motivational factors and more than one may exist for any particular person.
Christians usually do. They go to great lengths to explain away the obvious, searching for something to cast the unbeliever in a shadowy light that feels comfortable to them as they try to justify their faith.
Perhaps the most common reason for choosing atheism is not a personal conviction that God doesn't exist, but rather a negative reaction against religious practices one observed (or was forced into) as a youth.
You continue in the notion of "atheism as a choice"... beating a dead horse in hopes it will gallop for you.
the Problem of Evil... the fear that theism may be true...many or most theists are stupid, low-class, and gullible.
How about, because the mass of evidence sways logical, reasoning people to disbelief?
how many "strong" agnostics are out there?
That would be me. I didn't arrive at agnosticism lightly, or by choice. It took me about five years of reasoning, examining, pondering, asking, listening, discussing, and meditating to finally reach the point where I could call myself an agnostic. It was not a particularly welcome designation; simply the result of my thoughtful examination of reality.
I do so get tired of seeing atheists/agnostics cast in this shadowy light you're trying to perpetuate here. It is as misrepresentative of the facts as it is to say that most blacks are lazy, most Mexicans are thieves, most whites are bigots, most women are masochists.
As you will have perceived by now, I don't like the tone of your post. Oh, well...
COMF