When I think of my favorite books, they aren’t about characters that live happy, healthy lives. Likely, the main character is a poor, unfortunate soul who endures endless trials and tribulations.
He or she might have it all and lose everything or have nothing and everything to prove as life evolves from bad into worse.
We all have moments in lives we can draw upon to identify with these characters. We are rooting for them, and feel the tension as they fall and joy in their successes, no matter how small. We read on, knowing that something else terrible will likely happen -- wanting to know what happens next, and how the character gets itself out of the terrible mess.
Readers love suspense and failure and the ultimately satisfying resolution. So don’t have them follow a character with perfect family and a wonderful life. Introduce them to an orphaned boy who gets shuffled off to relatives to live in a closet under the stairs, a human girl who becomes involved in a love triangle with a werewolf and a vampire, or a boy-turned man who endures unrequited love upon a moor, and so many other characters who have so little to lose and so much to gain and never give up.
Think of the stories you remember best and write down what you loved most or connected with about them. Likely it will be for their unfortunate circumstances and the tenacity that drove them through it to the end as the tension got worse and misfortune fell time and again, calling for personal sacrifices and courageous acts with uncertain outcomes.
When revising your current work-in-progress, consider how you’ve handled your main character. Where are they coming from? Do they have a compelling problem? What have they got to lose? Mull this over, consider worse possible scenarios and then raise the stakes!