For me is when the Author said in the preface the whole story will be in first person view. But there are always a few lines or paragraph of third person view in the chapter. It's painful to edit the raw, if not just delete the whole thing. There are also sometimes many lines that are not necessary.
Unncessary descriptions of things. Unnatural dialogues that sound like written* by a bot who never had personal interactions (authors are introverts, sure, but they should at least be good at making fake convos lmao). False triggers.