"Different cats don't like certain litter. They also don't like an unstable floor, no animal like's unstable floor. So if you put a thin piece of plastic down under a litter box and the cat walks on it and starts to slip, they don't like that. Any animal doesn't like an unstable floor."

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I want to make sure to fix these obvious things - like keeping the box CLEAN! Another thing that might affect this [cats going outside the litter box] is if you put the litter box in a laundry room where people are walking by there all the time, the cat might feel kinda too exposed. When you gotta poop, you know, it takes a little longer. You want a little more privacy.

— Temple Grandin