No one's picture perfect. Everyone's got a dark side. And your novel's characters need to show theirs.
A couple of weekends ago I worked on bringing out the flaws in my characters. I was finding ways to make my good guys (my two protagonists) flawed. This involved everything from showing their selfish side, making them run away from things they are too scared to confront, and the odd weird things they do in their everyday life - not just decidedly 'bad' characteristics, but definite flaws. One of the girls is slightly OCD, for example.
Not one person is completely evil or completely good; it is our decisions that make us both. There's always more beneath the surface, and your characters would not be human unless they showed their flaws.
You don't have to make the flaws extreme. Every 'good' teacher, police officer, mother can't all be secret drugs barons, alcoholics who beat their families, or benefits cheats. Human flaws come in many forms, and your characters will not be rounded enough if you neglect them of these.
"But the blind man in Apartment 1-A is blind in many ways, as are all human beings, even those with functioning eyes. They are blind to their folly, to their ignorance, to their history, to the future that they will make for themselves. A future born of self-loathing.”
Dean Koontz, '77 Shadow Street'
Not all flaws are permanent. Sometimes, needs must, when our situation forces us to fight for things and take on unpleasant characteristics. Is your character bloody-minded, always stressed, or impatient? Flaws like this could help our characters succeed.
Everyone has flaws. That's what makes us human.
P.S. Don't forget to make the bad guys have a good side too. They may be bad, but they're also human. There needs to be a glimmer of hope. Maybe the teen killer has an unbridled respect for his parents. Possibly the pimp has a love in his life he'd sacrifice everything for. Or perhaps the school bully volunteers for a charity at the weekends. Try it out and see what you can come up with.
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Born to be a Tourist
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