To be a champion, do you need a memorable finsiher?

No, to be a champion, you don't need a good finisher. Take John Cena for example, he's a past champion, yet his finisher is an unimpressive fireman's carry. Another example of this is Batista, he has a sit-out powerbomb as his finisher, not very *memorable*. Oh, and another example is Hulk Hogan's legdrop, he was a former champion, yet his finisher was just a signature move.