The promise of accumulating certain things, and the threat of losing those things seems to spur people to action:

• Money
• Status
• Respect
• Fame
• Power (more specifically, entitlement over the fate of resources and people)
• Relationships
• A feeling of accomplishment, of having made a difference
• Moral superiority, being proven good
• Being proven right, being able to say "I told you so."
• Unique, special contribution