1. A character who looks in a mirror (shop window or whatever) so that the author can then describe them. So done to death.
2. A dream sequence where the reader is misled into thinking it is real, only to have character wake up and "Oh, it was all a dream."
3. Women characters who all seem to be weepy and incompetent in a crisis. Geez, women have kept the human race alive through the worst of times - very few are hysterical in a real crisis.
4. Rip-off plots. Books written to coast along on in the wake of a bestseller. You know, Da Vinci Code look-alikes. Someone writes a bestseller about being a drug-addicted, one-armed juggler living on the streets of London with a pet giraffe, and next thing you know there are dozens of books about drug-addicted, one-armed ju...
5. A mass of truly horrible characters none of whom I can empathise with, doing truly horrible stuff, none of which I can sympathise with. You've gotta offer me something better than that to keep me reading.
6. Women characters who, when together, never talk about anything but their relationships with men and clothes/fashion.
7. Male heroic figures who never care about all the killing they do.
8. Villains who have no purpose to their villainy except to be villainous. Why? What's the pay-off ?
9. A character that is too like me. Please, I wanna read to get away from it all...
10. I don't mind books that make me think. I don't mind books that leave me up in the air to draw my own conclusions about how everything turned out. But I do loathe books where I simply don't understand what the hell is going on and where I don't have enough clues so that I can even guess. And no, I never did get past the first page of Ulysses...