Depends, if I'm reading a series of books I want and expect some type of cliffhanger ending to each, but on the last give me the worst possible outcome and I put the book down happy as a clam. Why? Because I like the whole idea of imperfect life and imperfect resolution to a problem. That being said though, I do enjoy the occasional happy ending. Switches things up a bit for me and is the opposite of what I expect.