Herd mentality, mob mentality and pack mentality, also lesser known as gang mentality, describes how people can be influenced by their peers to adopt certain behaviors on a largely emotional, rather than rational, basis.

What does herd mentality mean?

: the tendency of the people in a group to think and behave in ways that conform with others in the group rather than as individuals Stock investors, riveted by recent market gyrations, need to resist emotional responses and the herd mentality when investing …—

What is an example of herd mentality?

For example, suppose that a family is walking down the street looking for a restaurant to have dinner. If they pass a restaurant that is empty and one that is relatively crowded with patrons, they are far more likely to choose the crowded one, on the assumption that it's better because there are more people there.