The mathematics of queueing theory enables a decision-maker to model the behavior of a queueing system. Mathematical equations are used to calculate the time spent waiting and the number of customers waiting. In some situations, if the lines are too long, customers may go elsewhere to be served. In this case the queueing manager is interested in the number of customers lost due to long waits. Generally, if the waiting time seems excessive and customers are dissatisfied, a manager will explore cost-effective strategies for increasing the service capacity by adding more servers or increasing the speed of service.

However, raw numbers fail to tell the whole story. The experience of waiting in line is influenced by the waiting area environment and our expectations as to the length of the wait. Imagine having to wait standing up in a dentist�s office for twenty minutes, while a patient is screaming in an adjacent examination room. Now imagine an alternative wait in comfortable chairs with access to the �latest� magazines for a variety of customer tastes. For your ten-year old child there is a video game machine, and the area is sound proof.

Many companies (Disney is one example) have become expert in understanding the psychology of waiting. Waiting in a line that is moving seems less boring than standing still in the same spot. TV monitors with engaging pictures help keep visitors� minds off the clock. In addition, if they can see and hear some of the excitement of those who have completed their wait, anticipation increases and waiting seems worthwhile. Lastly, expectations are a major factor in determining customer satisfaction. If customers approach a line and are told the wait will be fifteen minutes, at least they have the information to make an informed judgement as to join the line or not. If it turns out to be less than the quoted fifteen minutes then they are pleasantly surprised.

Another dimension to the psychology of waiting relates to fairness. It can be very upsetting to see someone arrive after you in line and end up being served before you. This can happen if there are two separate lines. You might get stuck behind a customer who has a complicated request that takes a long time to service. As a result, people who have joined the other line even after you might ending up waiting less time. Many organizations have addressed this potential inequity by creating one line which all arriving customers enter. Thus, anyone who arrives after you must be further back in line and cannot begin service before you do.