Today, I've seen an answer edit, which "corrected" two perfectly spelt words into wrong spelling. These two "corrections" were all that was changed in the answer. The answer was not mine. Also I can't be sure, but it didn't feel like a vandalism to me, I think this could be a honest mistake.
It's not often, when you see an edit that is clearly and totally wrong, most of the time it's quite subjective.
I'd like to know, what do you do, and what one expected to do with perceived "bad" edits? You can't flag an edit as far as I know. Should be they just let be?