Sometimes in stories what the major character wants is a big mistake. Not a mistake in storytelling terms, but in terms of what the character needs to learn. She firmly believes something is worth pursuing.
But she learns that she is wrong.
What she wants will be revealed as utterly false or superseded by a deeper, more urgent goal. In stories like these your basic story structure must be carefully handled so that you deliver a satisfying read, not a broken one.
There are several ways to play bait-and-switch with what the character wants:
Transcendence
This is when the character is placed in a unique position to sacrifice a personal goal for something greater. This may be a classic case of a moral dilemma, as in: Will the character give up a strong ambition for something larger than himself? In these stories, the ordinary–or the self-obsessed–person rises to heroic action.
Coming of age
Switching out the character’s driving desire is a classic strategy of coming of age stories. Your young character (or sheltered young adult) longs for something that is unworthy of them. (But not too unworthy, or it may be difficult to establish empathy with them early on.) She is naive in some basic, forgivable way.
Dorothy in The Wizard of Oz yearns for the excitement of distant lands. But in time what she desires is simply to go home. To put this approach in simpler terms, the character learns “what matters.”
The false ambition
The trick here is to make the first goal implicitly worthy. The story set up should provide a context within which we root for the protagonist’s goal. Make it a universal desire. But let other characters belittle the ambition. We establish empathy partly in reaction to mean-spirited obstacles. But the reader isn’t thinking deeply about the goal at this point–exactly the same position as the protagonist.
The character then embarks upon a journey of self discovery. And another goal gradually supplants the first. The character becomes someone capable of a larger vision.
As the story unfolds, more discerning characters cast doubt on the goal. But they aren’t to be trusted, perhaps, because they have their own agenda. The hero listens, but can’t give up the goal that has defined her. At this point the reader may well be ahead of the character. We know this is a fool’s errand. She does not.
This kind of story is tricky to plot. You’ll have important choices as to when the character intentionally abandons the false ambition. Plot point two, in film making terms, is a good place for a grand reversal. At this point, you must have a worthy goal lying in wait, a call to higher moral purpose that has been growing on the character. But let the reader still doubt whether the character can make the transition. This happens at the climax. The hero gives up the false desire and irrevocably acts on the greater one.
Some stories cry out for a bait-and-switch story goal. When handled with finesse, they can add an extra layer of interest to a character-driven story.