The term 'THEY ARE NOT RETURNED PROPERLY' can be summarized by the four-letter word 'ACES, ' which stands for 'Accounts Receivable Errors and Shortages.' This term is used to describe situations in which accounts receivable are not returned properly, such as when a customer fails to pay an invoice or when a customer pays an incorrect amount. In these cases, the business must take steps to correct the error and recover any lost funds.