There are generally two schools of thought on how to write a story. There are “pantsers” and “plotters.”
“Pantsers” are those who don’t outline before writing. They start writing and see where the story goes. “Pantsers” are very brave, in my opinion.
“Plotters” are those who outline the story before they even start writing the first word. These are the kind of people who read instruction manuals for any new thing they bought, before even turning it on. Heck, I don’t even turn it on unless the first instruction in the manual says, “1. Turn it on.”
I am a “Plotter.” Some say following an outline makes a story formulaic. Having a set of parameters within which to operate and create makes a story “cookie-cutter” and….well, formulaic.
The argument of course is, one can take a form and fill it with any of the wildest content one wishes. The form does not make the story formulaic. I would also argue that we the audience respond to formula in story.
Dances With Wolves is absolutely one of my top five favorite movies of all time. It is sublime and near perfection in my opinion. It is in the “Western” genre. People who like Westerns probably went and saw it. People who like Westerns expect there to be certain things in Westerns, like horses, shootouts, cowboys, native americans, no internet.
Avatar is a pretty good movie. It tries to be Dances With Wolves on another planet. It is the same story, essentially. It is science fiction. People who like science fiction probably went and saw it. People who like science fiction expect there to be certain things in science fiction, like science, aliens, other planets with life, internet.
Point is, elements that make up those two, and every other genre, are the formula for those genres. Doesn’t mean you can’t mix them, Cowboys and Aliens, meh, Firefly, yeah! But, even the audience knows on some level what is supposed to be in there when they pick their favorite type of story to consume. If I went and saw Dances With Wolves and half way through the movie an alien landed and tried to help John Dunbar with his neighbor problem I would be shocked and disappointed to say the least.
This doesn’t mean there couldn’t be a movie about just such a thing happening, but if I go to see a Western, it is going to be jarring if something typically “Non-Western” shows up.
It is fine to bake a chocolate cake and add hot-sauce with the eggs and milk, but you know, whatever.
Where was I going with this? I don’t know, I “pantsed” it.