The bandwagon effect is a psychological phenomenon whereby people do something mostly because others are doing it, often ignoring their personal principles or underlying evidence. It derives from the term “hop on the bandwagon,” in which people become interested in or follow an activity or cause that has recently gained popularity, often to gain acceptance by or recognition from others.
The bandwagon effect is commonly seen in politics, consumer behavior and sports. For example, a person may vote for a politician based on how the majority is voting to be part of the apparent winning side. The bandwagon effect can increase the politician’s lead primarily based on an information cascade of popular opinion despite possible conflicts with personal beliefs or contradictory information.
The tendency to follow trends and fads occurs because people gain information from others and desire to conform. In addition to the bandwagon effect, the practice of thoughtlessly following others can lead other psychological phenomena like groupthink and herd behavior. These social behaviors can obstruct critical thinking, hinder objectivity and promote cognitive bias.