Failure

Just like nobody enjoys a perfect character, no one likes a character that always makes the right choices and succeeds
If your character always succeeds, where’s the tension, the worry that they might fail? Without that, readers get bored.
A story needs fear that the character will fail/die/be beaten in order to keep readers flipping pages.
Even if they think they know where the story is going, they want to find out how they’ll get there

 How do you make them fail? 

Look back at their list of faults and flaws. Which of those can you use to put them in a situation where making the right choice will be difficult?
In “What We Saw At Night” Allie doesn’t tell the police what she saw because she’s afraid of getting in trouble for being somewhere she shouldn’t.
Why was she out at night? Because she has a severe sun allergy and has started taking risks because she thinks she won’t live very long.

How do you avoid nonsense failure?

Does it make sense in real life?
If some guy told you he was sneaking into your room to watch you sleep at night, you’d freak out. Bella, though, was totally cool with it, which has garnered criticism.
Would two parents ever actually split up twin girls and never let them see each other for their own selfish reasons like they did in The Parent Trap? I highly doubt it.
When helping characters make decisions, make sure there’s a good reason for what they choose. Lean on that backstory you crafted.
Do their fears influence them?
Have past hurts caused them to mistrust others when they shouldn’t?

What character failures have left an impression with you?