Amazon has blocked the accounts of customers who return items too frequently, without prior warning. This move has sparked controversy. Amazon spokesperson Christine Högner explained: "We only close accounts after detailed and comprehensive reviews in special cases." Accounts are closed when customers do not "exhibit purchasing and returning behavior that one would expect from a consumer." When asked about what exactly constitutes too frequent returns, Amazon did not respond. Thus, Amazon users still do not know what kind of behavior could lead to their accounts being blocked. From a legal perspective, Amazon's measures are unobjectionable. Businesses have the right to choose with whom they conduct business. Therefore, it is permissible to refuse undesirable customers. Other online stores also use account blocking as a way to combat the abuse of return services in order to protect their interests. The difference lies in the fact that generally, they will notify the relevant customers in advance.