 The customer oversimplifies the situation by not taking into account all the unfortunate events that might have happened to the waiter which made him/her become rude at that moment.Therefore, the customer made dispositional attribution by attributing the waiter's behavior directly to his/her personality rather than considering situational factors that might have caused the whole "rudeness".Self-serving bias is attributing dispositional and internal factors for success, while external and uncontrollable factors are used to explain the reason for failure.