People are not easy. You can’t put them in a box within a few days of meeting them and expect them to think and act certain ways for certain reasons. Even the ones you’ve known best and longest can suddenly do something unexpected and unpredictable.
Characters are also not easy, but not because they’re people. We talk as if they are, as if they have volition (“My protagonist won’t follow my plot!”), but they don’t. Characters are constructs, designs, concepts, models, words-in-a-row-on-a-page. They’re a set of choices the writer makes, not least of which is “Does this character belong in this story?”
One of the things that makes characters hard is, perversely, that they are simpler than people. A novel, or even a series of novels, isn’t long enough to actually cover all of a person’s experiences and reactions over even one year, let alone a lifetime. Writers have to leave things out; we are, in fact, told repeatedly to leave out mundane and repetitive things like what the character had for breakfast or how she mowed the lawn or the details of his daily commute…unless they are relevant to the story. A character trait that isn’t relevant to the story is, like the breakfast menu and commute, something that the writer can leave out (and usually does).
Relevant to the story is the touchstone that writers use, consciously or unconsciously, when we think about characters, who they are, and what they are like. There are four basic reactions the writer can have, looking at a character: 1) “This character doesn’t work in this story; I’m going to ditch him/her and make up somebody else.” 2) “This character doesn’t work in this story; I need to change the character so they’ll fit the story I want to tell.” 3) “This character doesn’t work in this story; I need to change the story so it’ll fit the character I want to write about.” 4) “This character is fantastic but doesn’t work in this story, so I’ll save them for some other story.”
Character-centered writers, and writers whose characters walk into their heads fully formed, usually have either the third or fourth reaction – they build the story around the character, change the story to fit the character, or save the character for some other story. Plot-centered and idea-centered writers tend to have the first or second reaction – they swap the character who isn’t working for someone who does, or change him/her to fit the story. Writers who “discover” their characters (i.e., make them up as they write) have to continuously decide whether to keep the current revelation and change the story, or keep the story plan and erase the newly invented aspect of the character.
But it is ultimately about the way the character and the story fit…or don’t. Slapping a random “flaw” on a character doesn’t work unless the flaw is relevant within the story. A flaw like greed or shyness may be effectively invisible if the character is the sole survivor of a plane crash in an inaccessible area, and the story ends when they finally reach safety. And is anyone going to notice if the giant barbarian swordsman is illiterate?
In some cases, the writer can adjust the story to force the flaw to become relevant – the crash survivor runs across a deposit of diamonds during his/her journey to safety, and has to decide whether to swap some of his/her food and water (survival) for the diamonds (greed). Usually, though, this kind of thing looks awkward and contrived and far too coincidental.
The kind of “character flaws” you actually want in a story are really the answers to the question “Why would this character have an unusually hard time dealing with this problem?”
The writer who starts with the story picks the protagonist by asking “Which person is going to find this problem particularly difficult, or be able to solve it in a particularly interesting way?” This writer isn’t going to spend much time focusing on the crash survivor’s greed, shyness, cruelty, or untrustworthiness, because all those character flaws depend on relationships with other people who aren’t around. None of those traits will make it harder for the lone character to survive. If the character has some other trait that will make survival harder or more interesting, like laziness or overconfidence, the writer will concentrate on that; if all the character has to go on with is greed or cruelty, the writer will kill him/her off in the crash and look for somebody else to survive to be the protagonist, somebody whose character traits will contribute to the story.
A writer who starts with the character gets to the answer by designing the problem to fit the character. Their question is “What problem (or dilemma, or choice, or obstacle) would be particularly difficult for this character to handle?” They usually know the why, because they know what the character is like. Or they know what aspect of the character they want to explore, or they want to take the whole concept of “strengths and weaknesses” out to the edge, and look at where the strength of “courage” becomes the weakness “recklessness,” or where the sneaky, underhanded, manipulative con man uses his “flaws” to outwit the real villain.
Ultimately, the character and the plot have to work together, and the only ways I know to make that happen are either to develop one out of the other (it doesn’t matter which you start with), or else at least look at both things together to make sure they fit.
“What problem (or dilemma, or choice, or obstacle) would be particularly difficult . . .” Aha: I see Lois McMaster Bujold’s favorite plot generator at work. Especially useful once you already have a character in print!
Having a character in print has less to do with it than knowing that character’s personality, likes, dislikes, strengths, and flaws really well. For a plot-centered writer, or for a writer who has to write their way into a character, it becomes easier to answer this basic question the more they’ve written about the character, because that’s not where they start. Character-centered writers like Lois generally start by knowing way more about the character than the plot, whether they’ve ever written about that character before or not.
I think flaws (or weaknesses) can also be both a reason for characters to need to cooperate with each other and a good source of conflict between them even when they’re on the same side/team.