"Final Cut" is the industry term for who has the final say on how the movie will be edited. A lot of financing deals require that the final cut go to the money people, NOT the director. Most films these days are tested in front of "test audiences" to see how an audience likes what you've made. This is sometimes very helpful, as you can get a sense of when the pace is too slow or when certain jokes aren't as funny as you thought they were. However, it can also be destructive, as a financier with final cut may use a note from the test audience to force you to make changes to the film that go against your gut. You ultimately have no right to fight against these changes because you have signed away those rights in order to get your money. As a film-lover myself, I always want to see exactly what the filmmaker intended.