When a commercial bank issues a loan, it is often agreed with the borrower that it can directly deduct the money with the right of set-off. The borrower does not own the money wrongly remitted to the borrower's account by others, and the direct deduction by commercial banks is not justified and reasonable. Its exercise of the so-called right of set-off cannot constitute an obstacle to unjust enrichment, but it should still be returned directly to others.
Offset has the following functions:
First, realize the creditor's rights. Creditors can realize their claims without litigation, judgment or enforcement. This is a private execution of one's own creditor's rights.
Second, simplify legal relations. In the case of unrealistic delivery, the debtor can only eliminate the transaction costs such as time and expenses of mutual performance through unilateral expression of will, so as to eliminate the debt. In a sense, all kinds of centralized settlement are also based on offset rules.
Third, the function of guarantee. If one party only exercises its own creditor's rights and fails to perform its own debts, then the other party cannot guarantee the realization of its own creditor's rights. Especially when one party can't perform the debt due to the deterioration of property, the other party can ensure the corresponding realization of its creditor's rights by exercising the right of set-off. Therefore, in modern economic and social activities, guarantee is an important function of offset.