"In most cases programmers make an error in the last line of similar text blocks."

I've noticed something similar in prose. When there's a sentence in a paragraph that should be cut, it's disproportionately often the last one. I've seen this in my own writing and in other people's. Interestingly, it's particularly noticeable in the writing of Wodehouse; these bad final sentences are one reason his later stuff is not quite as good.