When a character starts out a story, he or she has a GOAL. They want SOMETHING. And the reason they want this is because they want things to change.
The character's goal represents an improvement over their current circumstances, or a return to a situation when things were better than they are now. This is why they hold onto their goal so tightly when they experience setbacks and turmoil throughout the story.
No matter what the goal is, there is an emotional reason underlying it.
My favorite example for this topic is "Mrs. 'Arris Goes to Paris" because it's so simple and straightforward, yet emotionally appealing. It's a book I read a zillion years ago, and I remember it being made into a movie starring Angela Lansbury.
The title character is a charwoman who wants to buy a dress from a French designer, and she's worked very hard to save the necessary money. Her goal is to go to Paris and buy a designer dress.
Now when you think about it, it's not likely she'll have any opportunities to wear that dress, because her lifestyle is a simple one that doesn't include gala events. The garment will probably hang in her closet, never to be worn. Is it really worth scrubbing floors all day long for something so completely frivolous and useless?
For me, not so much. (That's why credit cards were invented after all.)
For this character, though, the answer is an emphatic YES.
What's important to remember is that dress represents beauty, and wealth, and a life that Mrs. 'Arris aspires to, even when she knows the dress will be the only thing she can acquire of that life. Owning that dress means she is more than a simple charwoman.
So you can see how the emotional underpinning of a goal is the driving force for a character's actions. Even if they don't consciously recognize this connection, it is still what spurs them on, even in the face of adversity. It's not a simple, "it would be nice if. . ." kind of thing. It's a yearning, a strong one. It motivates the character. In some cases, it defines them.
Once you know what a character's goal is, and WHY it is important to them, it is easier to plot your story, because now you know what they are willing to do to achieve that goal. Later, when the character discovers their underlying emotional need has been fulfilled, or it has changed along the way because of their growth, they are finally able to relinquish that initial goal. Even when it has motivated their actions throughout the book.
Recently I couldn't seem to figure out my heroine in the story I was working on. I knew what she wanted to do (retrieve something), but I didn't really understand why, or what that item represented to her. I also couldn't find the right name for her, so I kept auditioning different names, and character traits, when what I actually needed to do was understand WHY she wanted this particular item so badly.
It finally occurred to me, in one of those random moments that make me believe writing is 85% magic and 15% voodoo. And once I realized why she was so intent on this goal, and what it represented to her, her name instantly occurred to me, along with her personality.
She wants to be free of the burden of taking care of her family's craziness, along with the business they want her to run. Even if she can only have this freedom for a short time, she wants to experience a carefree lifestyle, and she decides she can accomplish that by retrieving this missing item.
So now when I get stuck, I'm going to interrogate my characters, to make sure they tell me ahead of time what it is they want, deep down, so that I can make sure they get it.
Before that, they're going to have to work hard. And they're going to experience some adventures they never would have anticipated when they set out to achieve their goals. There will be growth, and change, as well as emotional satisfaction.
And while that's happening, hopefully there will be an entertaining experience for readers as well.
So what drives your characters? Are they aware of why they want what they want? What are they willing to do to achieve their goals? In a "Goal Cage Match", who would win--you, or your characters?