There are so many potential motivations and complexities when creating a villain, it can be easy to get caught up in evil and not have enough true character development. To make the process simpler, here are some questions to establish parameters. Each question can be explored more deeply for the “why” behind the answer. Try going for an instinctive “yes” or “no” or a one-word answer, then take the time to explore the questions you struggled with and the ones you were surprised about.
- Does s/he want money?
- Does s/he want fame?
- Does s/he want power or control?
- Does s/he want revenge?
- Does s/he act out of love or passion?
- Did s/he have a traumatic or difficult childhood?
- Does s/he enjoy the suffering of others, or does s/he view it as a sacrifice that must be made to achieve the end goal?
- What relationships has s/he had—past and present (family, friends, lovers, children etc.)? Bonus: How have these relationships pushed them towards evil?
- Has s/he ever lost a loved one?
- Why does your villain believe that s/he’s right?
Few villains believe that what they’re doing is wrong (if they’re fully aware of the immorality of their actions, there must be a reason they decide it’s worth the outcome). They’re strongly motivated to achieve an end goal, so deciding that goal will be the most important launching pad to answer these questions. That goal may be straightforward–kill the hero, establish a new world order, rid the world of imperfection, etc.–or it may be more convoluted and personal. The villain doesn’t need to understand their own motivation, but the reader should be able to glimpse that sliver of underlying truth.
Write hard.
Be evil.
Sarah Brubaker 
Interesting article. Here are a couple other thoughts. Is he or she religiously motivated. Is he or she mentallly Ill.
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