Even if the bank card can't be traded normally, the identity and authorization of the bank card holder can still be verified by the password or signature, so as to ensure the security of the account and funds and prevent others from stealing or fraudulently using the identity of the bank card holder.

When the bank card can't be used normally, the password and signature can also help the bank to confirm the validity of the bank card and find that the card is damaged, stolen or other security problems. Therefore, when the bank card cannot be used normally, it is still very important to enter the password or signature verification method.