It's like this.  Imagine a character that seems to be the Ultimate Generous Person.  He gives money to charities every month, sponsors needy children in Uganda, donates a pint of blood every year and what not.  But, how is he going to act when the stakes are high?  If, say, he gets in the middle of a nasty, vicious divorce and his wife claims the house, will he give it to her generously or will he struggle to keep it?  How generous is he really, then? 

Under pressure, a character reveals his true nature.  If this character had a Motivation of "Help," he'll give his wife the house—even if she was a nasty witch.  But if our character's Motivation is actually "Hinder," you'll bet he'll do anything to obstruct his wife's goals.

"High stakes" is an important part of how a character reveals his nature.  The other important part—as the above example shows— is conflict.  "Conflict" means, "the direct opposition between two characters' wills and the struggle this opposition generates.

(CONTINUED)