You can give your players incentive to do things, but if it’s not the incentive they’re looking for they will probably demonstrate it by their in game actions. Some examples of player incentives include:
The Opportunity Crunch
No, brutal, soul-sucking, marriage-destroying crunch mode in game development isn't a privilege or an opportunity. It's idiocy.
Starcraft 2: Rush Analysis
I write a program to simulate different strategies in Starcraft 2, to see how they compare.
Dear Hollywood: Do a Mash Reboot
Since we're rebooting everything, MASH will probably come up eventually. Here are some casting suggestions.
Joker's Last Laugh
Did you anticipate the big plot twist of Batman: Arkham City? Here's all the ways the game hid that secret from you while also rubbing your nose in it.
Final Fantasy X
A game about the ghost of an underwater football player who travels through time to save the world from a tick that controls kaiju satan. Really.