Characters, male, female, both, neither, green and purple spotted spongiforms from the planet Dvwabc. Don't care. If they don't drive their stories, I'm not going to read. Sure. A character can START a story in reaction phase. No agency. No ambition. But if that lasts much past the inciting incident then I'm an unhappy camper. I expect characters to have an arc. Meaning that they may start a book as a doormat, but within the first few pages of the book, I'd better see some hint that this person/these people will grow a pair(s) and eventually take the story by the throat and throttle it into submission. From this diatribe, you may fairly assume I do not read much literary fiction.
2. Deus ex Machina
Literal translation - God in (or from) the machine. It's a hold over from the Greek plays you read in high school. Medea. Her hubby throws her over to marry another, politically well-connected woman. Medea kills the children she had with the guy. When he comes gunning for her, the entire conflict of the play is resolved because Zeus (who has had zip part in the play to this point) swoops down from the clouds, picks up Medea and teleports her out of Greece and back to her father's court. The term Deus ex Machina is now used to describe events in stories that are too pat. Too facile or convenient. It's easy to have happen if your characters aren't driving their stories. If forcing your characters to earn their happy (or unhappy) ending isn't your cup of tea, you'll have to guard against Deus ex Machina. Cause when your out of the blue ending rolls around, there's a high possibility that the book will fly cause I pitched it.
3. I can ID the source material
We all have writers and stories we wish we'd written. But when you go to write your version of that story, if you haven't disguised the source material well enough, I'll see through the veil and that, frankly, makes me deeply uncomfortable. I decided to pick up a book, the first in a series that has done exceptionally well. Read the whole thing - admired the writing and the story-telling - but still felt a bit uneasy. A few hours after I'd finished the novel, it hit me. It was a rewrite of Buffy the Vampire Slayer. And I was done. Not that the books are a rip-off. Or written badly. I could just see through the clothing. Sometimes feeling dirty is okay. This, for me, isn't one of them. And it should be noted that I may be the only person in all of existence who feels this way about this particular series. Take that for what it may be worth. I am guilty of this particular sin, too. I wrote a thing. Entered it into a contest. When the scores came back, one of the judges had nailed the exact thing (down to the scene) I had used as inspiration for the novel. That rated an insta-shelve of the WIP. It may not be rational, but there it is. If I can change it up enough to get a few more light years between my story and the inspiration I might finish it one day.