I've always liked the bad guys in stories. I love hating them, and I love how they force the main characters into life-changing challenges. But sometimes, they just don't make sense, and when that happens, the story suffers. The villains drive the conflict! And they can drive that conflict right over a cliff if they're inept.
The Big WHY:
Villains need motive. They can't just be evil because that's what the story needs. They need a reason to be evil.
Take the witch in Rapunzel, for example. In the original tale, her neighbor sneaks over her wall to steal lettuce for his pregnant wife, and she decides that the appropriate price for this crime is handing over their child? Nevermind that these parents (who've been yearning for a child) agree to this arrangement. Why in the world does an old woman want to become a single mother to an infant? And if she wanted to be a mother so badly, then what was the point of the tower prison?
The writers of Tangled completely rewrote her role. Mother Gothel wants something that women in our society have been culturally programmed to want--endless, youthful beauty. (Take a look in the cosmetics aisle, and you'll see by the battle terminology that we've declared war on aging. You'll see words like defy, battle, defense, erase.) Mother Gothel doesn't want to take on the responsibilities of motherhood at her age, but she needs Rapunzel to maintain her youthful appearance, which is the most important thing to her.
So you can see how motive can make a villain more relatable and strengthen a story. We don't like Mother Gothel, and we take serious moral issue with her kidnapping a princess and locking her up in a tower, but we understand why she did it. And we also understand why she won't give that up without a big fight. She really is a great villain in the Disney collection.
The Little Why and How:
I call these little because they're important, but probably shouldn't take up a lot of time or attention. This is villain backstory. We're fascinated by the nature vs. nurture argument. We're frightened of that side of ourselves that leaps out and surprises us with its ruthlessness. Even if we don't act on it, the fact that we thought it is enough. So we wonder how someone can be so selfish, uncaring, belligerent, dishonest, or whatever the villain happens to be. Whenever there is an especially troubling news incident involving a human being terribly victimizing other human beings, our first question is why?
We go searching into the "villain's" backstory, the media overturning the tiniest stones in an attempt to answer these questions. This happens at such a rate that it threatens to overshadow the tragedy the person caused by sensationalizing the bad guy. But there's something within us that urges us to try to make sense of horrible events by understanding the person who caused it.
So readers need backstory for the villain. As the story isn't about the villain, and the villain will likely be overcome in the end, there doesn't need to be a huge focus on it. But be sure to give your readers enough to make sense of the villain's choices. In the case of Mother Gothel, she was minding her own business and staying young with the magic flower until the jerk palace guards came and stole it. She doesn't seem to be a horrible person at the beginning, just a vain one. It was her commitment to her vanity that turned her into a villain. And there we have it--a touch of backstory.
Villains Aren't Robots (unless they're Cybermen):
Finally, villains need a little bit of humanity. Something that reminds us that they're people, too. No one is purely evil, and only the most melodramatic of melodrama villains look into their mirrors, twist their long, curled mustaches, and consider themselves evil.
Good villains have codes and values. They have things that they cherish. Let's look at Mother Gothel some more. She could lock Rapunzel in the tower with nothing but a blanket, a pitcher of water, and a loaf of bread, because all she truly needs is to sing to Rapunzel's hair every few days or so. But Rapunzel is clearly well taken care of. She has comfortable furniture, ways to entertain herself, nice clothes, and even a nifty pet chameleon. On her birthday, Rapunzel asks Mother Gothel for paints that would require three days of travel. Now, I know there are some loving parents reading this, so be honest with yourself. Would you drive a day and a half, pick up some paint for your child's birthday present, and then drive a day and a half back? I'm thinking you'd expect your child to make do with whatever paint you can find within about a half-hour radius. Yet Mother Gothel agrees to it, and it's clear from their conversation that she's made the journey before. While she has a short fuse and stellar skill for manipulation, Mother Gothel has a soft spot for Rapunzel. She can look at her youthful face in the mirror each morning and say, "I've done bad things, but I'm not evil."
And really, isn't that what we all do to varying degrees? Maybe we haven't kidnapped a princess and locked her in a tower, but part of being human is racking up our pile of regrets. We generally think of a good person as someone who tips the scales to the side of virtue, the good deeds outweighing the bad. The thing is that we're our own judges, so we can nullify and justify whatever we want. So Mother Gothel might admit that it was a bad thing to kidnap the princess, but she had no choice. And sure, she's locked this girl in a tower for eighteen years, but really, all Rapunzel has been deprived of is the joy of cute shoes. Rapunzel has no idea what she's missing out there in the real world, anyway. Mother Gothel would not call herself evil. Good villains can justify their actions with noble-sounding rationalization. They just have a skewed world view.
Being Uncomfortable in a Villain's Skin:
As writers, and hopefully decent human beings, it's difficult to slip into a villain's skin and take a walk. (Did that conjure up "It puts the lotion in the basket" thoughts? Sorry.) Anyhow, when we're not evil ourselves, and we're taught to abhor evil, something about getting into the head of an evil person just feels wrong. But I'm going to encourage you to do it anyway. As writers, that's what we do. We write characters and experiences that come from our imaginations. Think of it as no different than an adult writer getting into the mind of a teenage character, a male writer writing a female character, a stay-at-home mom on an Arizona ranch writing about a high-powered business executive in New York City. We wouldn't flinch at making these characters believable and relatable and human, so don't flinch at doing the same for the villains.
Because remember: Strong villain = Strong conflict = Strong story.
Up next: Antiheroes!