Movie Sequels: Good or Bad?

Today, we are talking about movie sequels & when they are actually needed, rather than a blatant cash grab by the movie studios trying to milk the nostalgia of the original movie a little more. While some people will look at a movie and say that all sequels are an opportunity to continue the story telling experience, we wanted to take a more critical eye to the subject & see if there were times when a story should be left alone after one movie.

Question of the day: what movie sequel have you been the most frustrated by & why?