You can tell when something's not moving forward anymore. When the doubts you have about it don't go away.
At the end of the day, successful box office just means that more people saw what you did and liked it, and that to me is the most important thing. That a lot of people saw it and liked it.
I loved the Little Lulu stories, where she would fantasize that her bedroom rug would turn into a pool of water, and she could dive down into the center of the world.