For your question, credit cards usually have an available limit, which represents the amount of credit you can use. Credit cards are primarily used to purchase goods and services rather than provide cash withdrawal capabilities. Here are some reasons why credit cards cannot be used to withdraw cash directly:

1. Interest and fees: Withdrawing cash usually results in higher interest rates and additional fees. Credit card companies charge high interest on cash withdrawals and may charge additional fees.

2. Risk management: The risk management policies of credit card companies usually discourage large cash withdrawals. Withdrawals can lead to potential risks and fraud, so credit card companies restrict withdrawal operations.

3. The purpose of credit card: The original intention of credit card is to provide consumers with a convenient payment method for shopping at merchants. The withdrawal function is not one of its main functions.

Finally, although credit cards cannot be used to withdraw cash directly, you can use other methods such as cash prepaid cards to withdraw cash. Additionally, some credit cards may offer cash advances, but these typically come with higher interest rates and fees. Please note that specific policies and restrictions depend on the issuer of your credit card. It is recommended that you consult with your credit card issuer or bank for details. Hope this answer can help you.