Grapes of Wrath. It's been years since I read it, but I remember fretting when the Joads started to eat their salted pork after only a few days on the road. Save the pork for an emergency!
Having a character lose something important to their success really makes for an exciting plot turn. Maybe because it feels so high risk, I rarely do it in my own stories! I make the mistake of playing it safe. But, I've come to realize that I have to push my characters to the edge of failure if I want to entertain myself and others. They have to lose all their money, or all their pride, or all their yummy salted pork.
Take something big away from your protagonist early on if you want their success to be that much more satisfying in the end.
