Even if I buy a book and end up hating it with a purple passion, I don't usually return it, but, today, for only the second time since first buying a Kindle, I returned one. Normally, this doesn't happen to me because I always, always, always check the Look Inside before I buy, so I can make sure that the author didn't step on any of my pet peeves. This current situation, though, was just like the last one - I'd read the first book in a series and, having enjoyed it, clicked to purchase the second one without giving it much of a thought. Then, I opened the file and saw that one of my pet peeves, one that hadn't been used in the first book, on full display. (Note: I'm not elaborating on the pet peeve because it's just one of my little eccentricities and, in my mind, unimportant to the thread. Didn't want to derail the discussion on returning by listing out pet peeves.) What about you? In what situation do you decide to actually return a book that you purchased?