The reasons why cat nails crack as soon as they are cut:

1. It may be that the owner did not use cat nail clippers, or the angle is wrong, which causes the nails to crack.

2. It is also possible that the cat’s nails lack nutrients or moisture and are relatively fragile and easy to crack. If the nails are not trimmed in time, the cat’s nails are also very easy to break.

3. Cat’s nails have many layers, and the outermost layer will fall off regularly. If it does not fall off completely, the outermost layer will fall off when the owner trims the nails.

Methods to prevent cat nails from splitting in one piece:

1. The owner should trim the cat’s nails regularly and help the cat remove the nails that have not completely fallen off. Keep nails trimmed and don't let your cat's nails grow too long.

2. Pay attention to the cat’s nutritionally balanced diet, and provide the cat with more vitamins and water. Cats’ lack of vitamins and calcium will lead to underdeveloped nails.

3. When cutting your cat's nails, do not use human nail clippers. Cat's nails are different from human nails. When trimming, you should also pay attention to the fact that the nail clippers should maintain a 45-degree angle with the nails.