At present, I mostly write short stories. Back when I was a lad, I read something about writing short stories which said that a good short story has a twist or an unexpected ending. I think the article may have been written by Roald Dahl (who was famous for Takes if the Unexpected). Now, I've always subscribed to that. With only a few exceptions, that's the kind of story I aim to write. But I was reading the submission guidelines on a certain site, and one of the types of stories they say the see too many of is the kind with a twist ending. What's your opinion on the subject?