Like the Klingons, the entrepreneurial Ferengi have a great many wise sayings, an important subset of which is known as the Ferengi Rules of Acquisition. The First Rule of Acquisition is "Once you have their money, you never give it back." Thus, Klingon thinking goes, if a Ferengi does return money, he is acting most suspiciously.

This Klingon maxim embodies the general belief: Those who violate the rules of their own culture and do not observe their own virtues are acting dishonorably and are not to be trusted.