My oldest cat has a very definite sense of herself. She has rules of behavior – for herself and for me when dealing with her. When she was about 2 years old, just getting totally past the kitten stage, she started assigning herself duties.
Woke up this morning. I needed to pee, badly. Ran to the litter box. It was being used. Ran to the other litter box, it was also in use. Ran to the litter box in the bathroom. The door was closed. Peed on the floor.