A friend who is an avid reader recently told me she was disillusioned with the triller genre. As an action/thriller writer this made me a bit sad but with further reflection, I’m not sure she meant exactly what she said. I don’t think she was disillusioned so much as disappointed.
I think she actually liked psychological suspense or literary suspense and was approaching thrillers with the same expectations. That’s one way to walk away disappointed in a book.