Social Proof

Also known as “informational social influence”. Human decision-making behaviour that results from people noting and copying what other people do; for example because they want to avoid having to make a decision for themselves, or avoid the effort of acquiring the data needed to make a properly informed decision. It is often applied as a form of ‘heuristic’ - a quick and easy way to confirm that one’s behaviour is “acceptable”. (“Everyone’s already doing it, so I will too.”)