He Could Be Stressed
If your cat won’t stop pooping on carpet, then he could be reacting to a stressful situation. Cats are not the best at dealing with stress or change and this might be sending his toilet routine off kilter. If you suspect your cat is a ‘stress carpet pooper ‘, have a review of anything affecting him, such as a house move, a new pet or child in the household or a sudden change to his usual routine.
Other Behavioral Issues
Certain cat traits can also lead to poops on the carpet as they try to retain control. If a new cat has been brought into the house, your kit could well be marking out their territory. While marking with urine is more common, some cats will use poop to stake their claim. And, as cats are fastidious animals when it comes to cleanliness, a significantly less than clean, smelly litterbox could push them to find somewhere else to poop.