I said I would get back to this.
Let's begin with the assumption that a story's protagonist wants something, and that they have some sort of personal code, constraining what they will do to get it. If either of these is false, I'm probably not among the intended audience.
So a victory would seem to consist of more or less getting what they're going for, without becoming hopelessly corrupt in the process. If the means are true but the end fails, then we have the epic tragedy of the doomed stand. If the end is won but the means fail, we get the ironic tragedy of the hollow victory. If the ends fail because the means strayed, we get the classic tragedy of sin bringing forth nemesis; and, finally, if the ends fail and the means were vile but there is no particular connection between these disappointments, we get the literary tragedy of the book hitting the wall. So far, so clear.
Within a single story, all of these things may occur at multiple levels. The story itself, though, is one and only one of them as a whole. I want to look at one of my favourite kinds here - the first one, victory, or protagonist triumphant. But that covers a lot of territory yet. It can be uncomplicated and unconditional: Eddore destroyed and the Hell-Hole harrowed. It can be bittersweet: Sauron defeated, and many fair and wonderful things passing with Frodo into the veiled West forever. And it can diminish into a minor chord of utter accomplishment and heartbreak: Ged done with doing, all his gifts given, and carried a-dragonback home.
No, there is nothing straightforward or vulgar about victory.
One thing that is not straightforward in the crafting of it, is what the reader most ardently cares about. Can the reader be sure
the author will give them a victory this time? If so, where is the tension? And if not, why did the reader just spend their hard-earned bills for yet another unwanted reminder that life sure can suck?
Which brings forth a choice. One way, for the "tough-minded" reader, is to establish early on that the protagonist's success is in very serious doubt. They can lose. They can lose it. They might not win, or they might go so far off-beam that you couldn't care less if they won that way. But... but... they're not quite down yet! And at the climax of the story, if the author doesn't cheat, this version of realism pays its dividends in earned YAY AWESOME THEY WON! - or in OH NO NO NO SHIIIIIT! - power.
There are problems with this approach. It takes exactly one word to provide a substantial spoiler. Also, once a reader has got an author's measure, questions like, "Can Plain John Smith defeat an alien god - before it makes of the Universe a hell forever?!?" tend to answer themselves quite independently of their superficial probability. But presumably we care about the sub-goals along the way too, so each of these can offer its own unpredictable tension. "Will they win?"
is not an easy question, nonetheless, to sustain at greater length than the novella. Sword-and-sorcery, with its relatively low stakes and frequently dodgy protagonists, is probably the SFnal subgenre best fitted to ask it.
"Will they win?" is not really a good way to describe my approach as a writer. Nor the approaches of most of the writers I read.
This leads me on to the next approach - which asks arguably the master-question of science fiction as a genre. This is the question suggested by seawasp
's 'Kirking it' preference - How Will They Win?
I defer its delights for a further post.