In honor of The Hunger Games movies finishing up this last year, I re-read the trilogy (again), and realized (again) that when it comes to Katniss Everdeen, Suzanne Collins doesn't forget to consider Katniss's irrational side.
Often when we deal with characters, we spend a lot of time building their rational side. We look at their rational motives and try to make sure they are thinking logically for the story line. I know I have spent hours trying to brainstorm and pin down the logical thoughts in some of my characters' heads. But considering how your character can be irrational can provide plenty of ideas for you to play with.