With my own cartoon, it was just me being goofy by myself, but when it comes to an animated film, you're working with 45 animators and assistant animators. It's a whole different ballgame.

Gary Larson
As for the reasons behind my retirement, they mostly center around simple fatigue and a fear that if I continue for many more years my work will begin to suffer, or at the very least ease into the graveyard of mediocre cartoons.