There's an old Jewish myth (actually a collection of related myths) about the golem, a man-shaped creature made of clay, created by a rabbi who was wise and holy. The golem remained inanimate, merely a lump of shaped clay, until the rabbi wrote one of the names of God on its forehead or on a slip of paper placed in the golem's mouth.
I think this is a nice metaphor for any creative act, and especially appropriate to writing. We gather together our raw materials (ideas about setting, characters, a dramatic scene and maybe a theme), shape them into a story and then, by our writing, breathe life into them. The mythical golem cannot speak; we also must give our story golem a voice.
In other, less prosy and off-topic words, we build stories by hand. We assemble them. At each stage of the process, we make decisions about the structure, shape and purpose of our story. With each decision we make, with each path we follow, we eliminate other possible paths, other possible shapes of our story. There are consequences to our decisions. Orson Scott Card refers to this as the "cost" of the decisions, and I think that's a useful way to think of them.
There is no perfect, Platonic ideal method of storytelling. Every storyteller (that is, every writer) has a unique reading history and therefore an individual vision of what a story is when properly written. That's the writer's voice. Even so, no matter how much we have read, we don't automatically have a fully-formed way of telling every story that we think of. We have to find it. We have to assemble our story method the same way we assemble our story elements. Which means turning our backs on any number of ways to tell the story.
I think that a lot of my own writing time is devoted to rejecting ideas, toying with possibilities and then abandoning them because, while they might work for some other writer or some other story, they aren't right for what I'm doing. And the more decisions I make, the more I hem my story in, limit the possible actions of my characters and kill off hosts of alternate endings. I make a sort of rule system for the story and have to obey those rules, focusing on what choices I have allowed myself.
On the whole, I think this is a good thing, because it helps me know what I'm doing while I'm writing. I've tried to rule out things that will harm the story. Herman Melville, in "Moby Dick", takes every other chapter to write an essay about whaling, or the color white, or whatever. Some of this is fascinating reading. Some of it is not. All of it pulls me out of the actual story. This is the cost Melville pays for sharing all his extensive research.
In my own book, I put in some long passages (not chapters, though) about religion, theology, history and architecture. I told myself this was setting and, since it interested me (and because I'd done loads of research) it would interest a reader. Maybe it would, but it came at the cost of pushing the actual story away from the reader, and that was a price I didn't want to pay, so I cut reams of text.
When my agent and I first discussed my book, one of the ideas he threw at me was to change it from a first-person narrative to a third-person narrative. This would solve one problem (that the narrator has to be present for almost all the action no matter which characters are involved), but at the cost of losing the immediacy of the protagonist's voice. That was too high a price, so I rejected the idea right off.
This is a long, rambly post, for which I apologize. My point, if I have one, seems to be that for each story we write, there are a large number of similar stories we chose not to write. Somewhere out there in the aether is a version of my story as told by the protagonist's wife, and also a version told by the villain, and also a version in third-person that flashes back and forth between Denmark and Germany, a version filled to the ceiling with details about 16th-century Europe and the Reformation. That I won't write any of these versions sometimes depresses me, but life is short and I think, well and truly, that I've chosen to write the version I will like the most.