I think cats feel that doing one’s business is embarrassing. I say this after observing some of Simba’s mannerism when doing it. The look Simba has when making a number or the way he covers it up or even when I go near his litter tray to clean it, indicates to me sense of shame at what he has done. The very fact that cats leave ‘gifts’ around if their litter box is not clean, also shows that they are very aware of the ‘dirty’ aspect of poop and pee. And just why should a cat’s litter box must be placed in an accessible yet private space?