A writer writes what interests him and what he can manage, and what he can make live, as Flannery O’Connor said. So my reaction to someone saying “You must!” or “You should!” or even “Hey, why don’t you?” is basically to sort of shrug and politely walk off and do whatever I want to do. It’s nobody else’s business, really, and even if I happened to agree with one of those “musts” or “shoulds” what would I do about it, if my heart wasn’t in it?