9. Friends
Don't get me wrong, Friends is an American institution, but that doesn't mean that it didn't overstay its welcome a tiny bit. The simple truth is that when a formulaic sitcom gets to ten years old, it starts to show its age, no matter how good it is. Plotlines get recycled, characters become tired, and old relationships get revisited to try and revitalize the viewing numbers. Ross and Rachel are probably the best example of this in all of television. Will they, won't they? After they get together and break up and get together again enough times, eventually no one cares anymore. You just wish that they would suss out what they actually want and get on with it.