In modern Hollywood, there's nothing more unoriginally exciting than a franchise. They're the king of the box office; what a studio does unless they've suddenly decided they don't make money.
And everyone gets caught up in it; every time a new wunderkind director comes along, the immediate question is either "Will you do a sequel?" "Which franchise are you going to jump on board with?" Even Adam Wingard, the subversive horror director who'd made a name for himself sending up genre, turned to Blair Witch after his previous, The Guest, didn't quite excel at the box office.
But they're not infallible, never-ending conveyor belts of money. While the word "sure thing" is banded around a lot, when you've got hundreds of millions of dollars on the line and a bad word from an actor is the difference between success and failure, there's always a risk of massive loss. As we've seen this summer, plenty of projects marketing execs gave a thumbs up while dollar signs blinded them wound up being bombs, likely ending many emergent franchises.
So yeah, franchises may be the studios' go-to, but that doesn't mean any old series is a guaranteed gold mine. And it's not reserved to "wait, why the f*ck did they do that?" movies like Independence Day: Resurgence either; things audiences once loved can very quickly go sour. Just look at the long list of once-great franchises that crumbled based on just a single, shoddy decision.