As a few people have pointed out, there’s something missing from my discussion of religion as the leading source of atheism. I said that when you find a mistake in your religion, you have two options: either leave the church, or become a hypocrite. The possibility of correcting the church’s error is not really an option, because the church’s whole authority system is predicated on the assumption that it cannot make any mistakes in the first place. Acknowledging the existence of an error means admitting that the church’s authority is based on a false premise.
Some people suggested that the third option is to start a new religion, or at least create a schism, but I would include that as a sub-category under the heading of leaving your old religion. When you start a new religion, or a new branch of the old one, you’re saying in effect that the old one is wrong and therefore you’re leaving it. I got to see this a lot in the Church of Christ: each half of the church split would promptly declare that the other half was on its way to hell, because they were rejecting the Bible’s plain declaration that _______ (fill in the blank: “communion is/isn’t one cup”,”missionary societies are/aren’t a permissible means of spreading the gospel”, etc). You may be staying within the broad outlines of religion, but you’re leaving your original faith.