You make a film, and if you do it properly, you're putting put all of yourself into it—everything you know and whatever wisdoms and skills you might have accumulated along the way. But you don't really know how its going to impact, and it usually takes time. First of all people write about it in reviews, and there tends to be a consensus of what works and what doesn't over time, and then…somehow to some extent a film either impinges in some way on a culture or it doesn't. After a while, the audience starts to tell you what your film is.
In this FreshAir interview on NPR, George Miller points out that in the case of Fury Road, this whole process—where the audience starts to tell you what your film is—happened very quickly.
Almost as soon as the film was released, the Internet exploded. Everyone—from famous critics to average Joe bloggers—had an opinion, and a whole heap were positive. And that's where the fandom of Fury Road really began: cyberspace.
Fans showed their appreciation for Fury Road's thoughtful approach to the action movie genre by writing thinkpieces on anything and everything about the movie:
The movie's popularity helped contribute to the franchise's productions. There's a sequel (or a quintuple?) in the works, and there's even a comic book prequel, telling the story of Furiosa at the Citadel. Oh, and don't forget the 2015 video game, which lets fans experience first hand the movie's brutal world.