Restriction of Output; Although many studies have shown that incentive-pay systems significantly increase productivity, numerous examples have also been reported of incentive-pay systems that restrict output to arbitrarily low levels. This restriction of output problem is at least as old as scientific management. Taylor referred to the problem as soldiering and described several examples of work groups that had established arbitrarily low levels of productivity and pressured their members not to exceed these group norms 61 Evidence of group norms restricting productivity is sometimes quite obvious when new employees join a work group. The influence of group norms on the productivity of a new employees join illustrated in Exhibit 22. Within two-and-one-half weeks, the new employee's productivity increased from 32 units of work per hour to 74 units of work per hour. Then suddenly the employee’s productivity fell to 56, the same as every other member of the work group.