What Makes a Great Tutorial?

Tutorials are essential to every game experience. In that time we learn the game mechanics, the key players, and of course the main quest. The first few hours of a game can easily make or break our opinion of it.
So what makes a great tutorial? Beyond just explaining the controls, what do some games do that hook you at the start and keep you coming back?
A bad tutorial can be boring, it can be tedious and repetitive. But a good tutorial can be funny, insightful, entertaining, and give you a grea