When looking at literature there are two engines that drive narrative, plot and character.
Plot driven stories are often genre literature (horror, sci-fi, crime, etc) and are powered by a single goal. Destroy the one ring, survive the zombies, solve the crime, etc… While these work fine, character driven stories are far often held up as the superior from of narrative. There's a reason we remember Shakespeare's characters, they move the plot forward not just because they're questing after a magic MacGuffin but also because it is their interaction with the other characters that creates the conflict which drives the story. George Martin's work is similarly powered not by a single goal but by the friction between characters which in turn leads to the action of the narrative.
And it is conflict, in and of itself, that is at the core of story. No conflict, no story. That said, read Flannery O'Connor's "A Good Man is Hard to Find" and tell me how much of the story is driven simply by the "What If" scenario and how much of it is caused by the actions, emotions and desires of the characters.