Cats might have a perfectly good litter box (or two), but they may still poop outside of the litter box for no good reason. Then again, cats always have a good reason for doing anything although that reason often defies logic and common sense.
One reason cats might poop outside of the litter box is due to stress. Another could be if you moved the litter box or if it’s in a high traffic area so the cat feels it doesn’t have privacy. Then again, the cat might just be pooping outside of the litter box just because it can. That’s to show you that the cat has more power over your life than you do.