So a while ago, I ran into a wonderful quote from George R R Martin.
It reads as follows:
I still love all the characters. Even some of them who aren't very loveable. At least the viewpoint characters. When I'm writing in the viewpoint of one of these characters, I'm really inside their skin. So, you trying to see the world through their eyes to understand why they do the things they do. And we all have, even characters who are thought of to be bad guys, who are bad guys, in some objective sense, don't think of themselves as bad guys.
That's a comic book kind of thing, where the Red Skull gets up in the morning [and asks] "What evil can I do today?" Real people don't think that way. We all think we're heroes, we all think we're good guys. We have our rationalizations when we do bad things. "Well, I had no choice," or "It's the best of several bad alternatives," or "No it was actually good because God told me so," or "I had to do it for my family." We all have rationalizations for why we do shitty things or selfish things or cruel things. So when I'm writing from the viewpoint of one of my characters who has done these things, I try to have that in my head.
This relates to the post about villains I wrote a while ago, and more importantly, it does so in a manner more concisely than I managed.
When writing or crafting characters, it's important to remember that the villains almost never think of themselves in that way. The ones that do tend to come off as caricatures and kind of cartoony.
Characters like Cobra Commander, or Darken Rahl from the Sword of Truth, or hell, even frigging Jafar. These villains are hard to take seriously and hard to empathize with because THEY KNOW that there's no real reason behind what they're doing. They're doing it for plot, not because they actually want to.
And as an audience? As a reader? We can tell these things. Especially if you contrast them against villains who actually have motivations and don't necessarily think themselves the bad guys. We're talking villains like the Lord Ruler from Mistborn, the Red Hood from Batman, or John Marcone from Dresden files.
Villains who have their own driving motivations and (more importantly) their own set of rationalizations for WHY they're doing what they do are much stronger than those who do not.
The important takeaway from the Martin quote above is that most of the characters who are commonly considered to be villains DON'T wake up in the morning and ask themselves what evil they can accomplish that day.
They don't do this because real people don't do this (generally). It's important that your own villains reflect that. They need a logical motivation for the things they're doing. And the worse their goals? World domination or bringing about the apocalypse, the BIGGER and more powerful the motivation needs to be in order to make that seem remotely believable.
Think about your villains...your favorite ones. The ones that stay with you, long after you put down the book or turn off the movie.
What factors do they have in common?
Do they have motivations? Or are they just evil for the sake of being evil?