Quote from Zootopia director Byron Howard:
When you’re a storyboard artist here at Disney you have to be comfortable with your work getting thrown away. All of us who storyboard on this movie have done literally thousands of drawings that have wound up in the garbage, because these ideas come in and go out of the film very quickly. The idea is to be wrong as quickly as possible. We really try to try out as many ideas as we can, then when the right ideas click in, then you’ll see from screening to screening, the rest of the film will build around those key ideas.