Developing Rounded Characters: Filling The Gaps

When I talk to writers about their characters, what I often hear are simple motivations: “Daisy wants to climb Mount Everest” or “Phil wants to be a star.”
Problem is, those aren’t really “motivations” so much as “statements of their goals.”  There are a hundred reasons why Daisy might have become obsessed with conquering the peak, and all of them add different flavors to the story.  Is Daisy an out-of-shape businesswoman, used to taking over corporations on a daily basis, and she figures if she can afford to pay $30,000 to these package-vacation Sherpas she’ll have a great story to impress potential customers with at conventions?  Or is Daisy from a poor village in some distant country, having grown up feeling that the world has yet to acknowledge the tenacity of her people, and she’s determined to be the first of her people to climb Mount Everest without an oxygen tank?  Or is Daisy a thrillseeker, an Xtreme sports addict who thinks she’s going to live forever, who plans to snowboard down the west face of the mountain?
As you can see, even without a plot, these are three very different stories.
When you’re thinking of a story, you tend to think of goals, because hey, you want to write a tale about Mount Everest, so you need someone who wants to go there.  That’s a normal way of developing a tale.  But goals are not motivations.  Once you’ve gotten the immediate goal, start thinking about the gaps that person is trying to fill.
Most people have a gap in their development, an incompleteness that they’re relentlessly trying to fill by repeatedly doing something that’s self-destructive.  That stupid act fills the gap for a time (even if it never ever quite fills it).  There’s some insecurity they’re fulfilling, even if they can’t quite bring themselves to articulate what it is – and in fact, they usually can’t, because if they could acknowledge this deep feeling, often they’d fix themselves.
You’re not just looking for a character who wants to climb Mount Everest, you’re looking for the need within themselves that they fulfill by climbing a mountain.  And often, in finding that emotional resonance, you find the heart of the story.  (Stephen King is the master of this, and that’s part of the reason he’s so successful.)
Want a real-life example?  Let’s say we’re writing a story about a guy who falls in love with a demon, and so meets a terrible end in an alleyway.  You need someone who’s patently attracted to dangerous women, so you say “Phil’s really attracted to psychotic women.  That’s why he meets a demon.”
That’s not enough, though.  You have to ask, “What emotional gap is Phil fulfilling by dating dangerous women?”
Dig deeper!  The truth is that Phil is insecure and unaccomplished, and doesn’t feel wise at all.  By dating really unstable women – and he has to go wandering far to find women crazier than he is – he becomes their mentor, advising them on patently obvious things, and for a time he gets to feel like a guru.  That’s the gap that gets filled.  Now, that inevitably disintegrates (as gaps are wont to do), since he actually doesn’t like living with women who can’t keep a job, and in time his girlfriends come to resent his control-freak issues.  So he continually bitches about why he can’t find a stable woman, but then he finds a new crazy girl and things are okay for a time.
That’s an actual character, someone unique that you can build a rather fascinating tale upon.  (And one that may not involve a cheap death in an alleyway – would this Phil really be fulfilled by dating an aeons-wise demon who knows more about human nature than he ever will?  What will the demon teach him?)  But that involves really thinking beyond obvious goals, to the inner emotional state of the character.  Which, if you can do it, will lead to richer stories.