Hello, I think it is necessary to open a one-card account, in which 1000 yuan is reserved, which can enjoy many discounts and reduce some fees. Therefore, the staff will advise you to deposit 1000 yuan when you apply for a card.
If you have any questions, please open the homepage of China Merchants Bank in www.cmbchina.com and click "Online Customer Service" in the upper right corner to enter the consultation.