There could be several reasons why a cat might rub its poop on the floor:
1. External parasites: The cat's skin may be infected with parasites such as fleas and lice. These parasites can cause discomfort on the cat's skin, leading the cat to scratch. Regular external parasite treatment is necessary.
2. Internal parasites: The cat's intestines may be infected with parasites such as tapeworms or roundworms. These parasites can irritate the cat's intestines, causing it to scratch with its paws, and may also be accompanied by symptoms such as diarrhea. Regular deworming is necessary for cats.
3. Gland Inflammation: A cat's glands may become inflamed, causing redness, swelling, and pain in the surrounding skin, which the cat will likely scratch. You can apply iodine solution to the inflamed area. If the condition is severe, seek veterinary attention immediately.
4. Cleaning themselves: After defecating, cats may scratch the floor with their paws to clean up any remaining feces. 
If your cat exhibits any of the above symptoms, you can take the following measures:
1. Regularly treat your cat for external parasites. Common external parasite medications such as fipronil and imidacloprid can be used.
2. Regularly deworm your cat. Common deworming medications such as praziquantel and albendazole can be used.
3. If your cat has inflamed glands, you can apply iodine solution to the inflamed area to relieve symptoms. If the condition is severe, seek veterinary attention promptly.
4. If the cat is simply cleaning itself, there's no need to worry too much. If the cat is frequently scratching the floor, it may be due to discomfort caused by the floor material. In this case, you can replace the floor material or clean up the cat's feces promptly.
In short, if your cat is scratching the floor, you need to carefully analyze the cause and take appropriate measures. If the situation is severe or persistent, it is recommended to consult a veterinarian for help.
