In the study of Organizational Behavior, the landmark 'Hawthorne Effect' primarily established that employee productivity tends to increase when workers:

Conducted by Elton Mayo and Fritz Roethlisberger at Western Electric's Hawthorne Works (1924–1932), the Hawthorne Studies gave rise to the Human Relations Approach in management thought. The Hawthorne Effect: Refers to the phenomenon where individuals modify or improve an aspect of their behavior in response to the awareness of being observed. The studies revealed that workplace social dynamics, managerial attention, group cohesion, and the feeling that management valued their contribution had a far greater impact on output than physical working conditions (such as lighting levels) or direct financial incentives.