All character development boils down to one simple thing: the character starts out as one thing and ends up as its opposite.  That’s it.  If you never learn anything else about how to develop characters, learn that.  Whatever the character starts out as, they must be the opposite by the end of the story.  This is the promise you make to your readers.  Cheat them on this and they’ll hate you for it.  It means you haven’t followed through and that’s the worst mistake you can make as a story teller.  Follow through is everything.  Every story starts out with implicit promises to the reader.  They either fulfill those promises, by following through, or the story fails.  Simple as that.  So let’s see how this works in action.

First off, before we go any further, you need to know that this only applies to major characters.  Minor or secondary characters don’t need to change during the story.  In fact, they probably shouldn’t.  Too many characters shifting around can confuse readers, making it hard to know who to focus on.  Not every character can have the kind of depth that comes from true character change over time.  And they don’t need it.  It’s all right for your stories to be peppered with the happy barista at the coffee shop, the tough guy at the bar, the severe boss, all of who never change at all.  When the the reader reaches the last page they’re still the happy barista and the tough guy.  But your main characters need to make the ultimate shift.

One more thing to know: There is one exception to the rule.  Tragedy.  In other words, the character fails to make the massive change the story demands.  That means they never realize their true potential and they fail at their life’s purpose.  Lots of stories end this way.  Usually it’s the villain who faces this fate.  Sometimes it’s the hero, though audiences really don’t like this very much and you’ll have a hard time selling it.  Do it, if it’s the right thing for your story, but avoid making your hero the failure if you can, at least in the most important parts of his life.  He can not be perfect in all aspects of his life.  He might have a failed marriage or a gambling habit or drink heavily.  But the big changes are what we care about.

The story arc moves simply for major characters.  He or she goes from loveless to lover, ruthless to compassionate, selfish to selfless.  Now all you have to do is line up all the odds against them.  Make sure the story is almost maliciously keeping people from their goals.  As Eckhart Tolle once said “life is there to frustrate you.  That’s it’s purpose.” In fact, once you know this, it might seem like it can ruin the best stories for you.  But always know that deeper understanding of stories always leads to even deeper understanding.

In real life, we all start out as something other than we were meant to be.  It’s the same in fiction.  This is really the only type of story we care about as readers.  We only want to see the big changes in life.  Minor fixes don’t mean much to us, because we’re all trying to realize our own purpose .  We want an instruction manual on how to do it and that’s what stories give us.

Once you know this, you can easily analyze stories and figure out how they’ll go.  That doesn’t mean there won’t be twists along the way.  There should be, actually.  Keep us guessing.  Let’s take a look at my current darling, Game of Thrones, a story I’ve studied a lot.  Take Jaime Lannister.  He’s cold blooded, conceited, and selfish when the story starts.  He’s having an affair with his sister.  He throws an eight year old out the window to cover their affair.  He’s hardly a redeemable character, but that’s exactly what the story will do for us.  Expect it.  Here’s how.  He’s humbled during his journey with Brianna of Tarth.  When they’re captured by highwayman, he talks them out of raping her.  He loses his hand for his good deed.  I don’t have to read the plot summary on Wikipedia to know that Jaime is on a redemption arc.  As soon as he turned into a POV character in the third book, this was written in the stars.  For a story to really break through and touch millions of people, to rise above all the other stories being produced on the planet right now, it must deliver this big change for all the main characters.  Jaime must become a good man and try to make up for his past sins.  This is what we want and what we need.  A good author knows this.  He delivers every time on this front, even if he drops the ball in a few other places.

Do this one little thing and your readers will love your stories.  They’ll feel like they’ve taken a journey and discovered something deeper about your characters and more importantly about themselves.