[JohnWhigham]

Literally: it's doing something because others are doing it and that's it.

Developers have a massive proclivity to follow something simply because others have. We're talking everything from best practices to design methodologies to whether or not to include a semicolon at the end of a line. There's a reason for this: writing software is very hard to measure and quantify. It's not a physical thing like a bridge or an automobile. When we hear about some new paradigm/framework/language/etc. espoused by some blue-checkmark-wielding developer who works at Google, we pay attention because...he works at Google, and seems like a trusted figure.

Not saying this is good or bad, it's just how it is.