Herd mentality

Herd mentality means that people tend to think and act the same way as everyone else, especially in a group. If a bunch of people like a certain thing, then it's more likely that others will also like it. It's like a domino effect - when one person does something, it starts a chain reaction that eventually affects everyone. Think of a herd of sheep - if one starts running, they all start running! That's herd mentality.