Azkaban is the worst prison in the whole of the wizarding world. Most who have the unpleasant misfortune to go there usually don't leave... at least not in one piece. Fortunately, for Harry, Azkaba...
"But I don't want to go among mad people," Luna remarked. "Oh, you can't help that," said the Cat. "We're all mad here."
Detention has never been so fun!
"Your time is up, Harry James Potter. It is time to move on, from this world, and into the next. Remember what you have lost, but do not dwell on it. Now is your time of joy."