Answer: Illegal credit card operations. Credit card installment payments still have high credit requirements on cardholders. If you have late payments and obvious cash-out behavior when using your credit card, the bank will determine that you are a risky user. Banks themselves are there to make money. Of course, it does not allow risk-controlled users to pay in installments. If you don't pay back the money, the bank will lose a lot for small things. So I would rather not have your installment interest than give you the opportunity to pay in installments.