The behavioral school of management, however, holds that even though individuals experience increased happiness when their pay rises, the intensity of desire for wealth remains negatively correlated with psychological wellbeing. McClelland’s theory of needs, for instance, classifies employee needs into three: need for Achievement, Affiliation, or Power. Victor Vroom's theory holds motivation as a function of Expectation, Instrumentality, and Valance. Money thereby alone does not motivate, and the extent of motivation depends on the motive for acquiring wealth, in which psychological needs play an important role.