requoting shigeru miyamoto: "[...] I concluded that [what made people want to play a game again] was [...] the players being mad at themselves. so I would try to analyze how the game made players feel that way."

"the genius in how farmville has succeed in getting so many people addicted comes down to how it handles commitments on a player's time: every time you play farmville and plant a crop, you're making a commitment to come back during a 12 hour window or so to harvest your crop, or else you forfeit your investment."