Bandwagon effect — The tendency to do (or believe) things because many other people do (or believe) the same. Related to groupthink and herd behavior.
114 Decision-making and behavioral biases
Often we are faced with situations where our intuition misguides us. Cognitive biases are systematic patterns of deviation from norm or rationality in judgment. Many of these biases affect belief formation, business and economic decisions, and human behavior in general.