Defecting

The word defecting comes from mathematical game theory. It is customary for a person to follow through on a debt, favor or obligation. If they do not follow through they have "defected." In Mathematical Game Theory says that the next move a savvy person must make when a person has defaulted on an obligation is a tit for tat response. Once a person has defected they have established the fact they are unreliable and arbitrary in their ways. In order to bring the relationship back to equilibrium and fairness the merchant must use the tit for tat strategy.