A character knows about what they want. They are unaware of what they need. That want is external. Anna wants to gain control over her life's choices: relationships, work, pleasure. Even choosing which others she will serve. At the start of the twentieth century, that control was beyond a woman's reach — an unprivileged woman, anyway. What Anna needs is the confidence of agency that pursuing those choices gives her. Taking risks to get what she needs demands that she take action. When she believes in her newfound agency, she can act to face new opportunities and challenges with certainty and peace. The world around her becomes a better place.
A need for a character can surface in the aftermath of trauma or injustice. The character says, "I won't let that happen to me." They need self-respect and they want to achieve it through winning a contest. Unless that victory delivers on their need, though, even the win is likely to get them into more trouble.
Chasing a want, instead of a need, fixes things the wrong way. Make a character chase down their need, and you open their door to transformation.
A masterful twelve minutes on YouTube deliver a potent summary of how characters are designed through wants and needs. The podcast Lessons from the Screenplay uses the Pixar movie Soul as its example. (Seeing Joe discover his needs still brings a tear to my eye.)
Wants are the surface desires for a character: the new job, the new partner. Needs are the interior desires, unspoken but coursing through every decision. The richest needs can crush the lie a character's been believing about themselves, or perhaps shatter a mistaken belief in how the world works.
Thinking about the wants and needs of a character is a crucial start to developing and expressing a compelling person. This is not work to do only in fiction. Narrative nonfiction, or what's called memoir for many of us, makes authors uncover their own wants while telling us about their needs. Memoir calls on us to create characters, too. The characters are ourselves.
Your character’s flag flutters in the wind of their needs. Robert Ohlen Butler, a decorated novelist, called this a character's yearning. It's a motivation that determines choices, which lead to actions. Stack a few of those actions up and you get a character's behaviors. Time for a decision? Let it reflect that intangible need, that yearning. Those choices are shifting Anna's perspective; she grows.
If your story has plenty of plot, but not enough yearning, the characters look two-dimensional. They fall prey to becoming stereotypes. Then the answer to the why of the heroine's actions becomes something like, "Well, that's just what brigands do." The next thing you know, you've got a heroine who's a brigand but isn't a member of a gang, because it seems to suit the story. Some of the yearning in a brigand is knowing their place in a gang, then trying to improve on it while they hang around with the other brigands.
Deciding what you don't want to do is a start at learning what you do want to do. And what you need to do? It's attached to yearning. The delicious thing about yearning is it can bubble up in you (in a memoir), or in your characters. It's a discovery, and that doesn't mean some static rumination in a secret fortress of solitude.
The crisis of an opponent's attack serves up the means to discover yearning. "I fought back," Anna might say, "because I saw everything a woman could lose if she did not." There's the memory and pain of injustice and grief. The struggles of fighting back lead her to peace, a battle that we want to watch because we know the yearning that is at stake. Whatever a character will do if she doesn't get what she needs is the worst thing that can happen. She courts that dangerous thing on the way to achieving her yearning.