As an example, Masten Space was created after SpaceX, but the ideas "build a little, test a little" predates both of these companies.

SpaceX has built on top of lots of existing ideas - commerce instead of government services, simplicity instead of performance, vertical integration instead of spreading orders, testing philosophy, re-use...

> SpaceX has built on top of lots of existing ideas

Everything is built on top of lots existing ideas, nothing is created in vacuum.

avmich mentioned it because otherwise there would be a pedant asking “why are you implying that SpaceX invented these ideas?”

I don't think anybody iterates as fast as SpaceX.