It's about keeping them going by offering new wrinkles in the play. If designers run out of play before they run out of story, the game dies.
http://www.wired.com/gaming/gamingreviews/commentary/games/2009/03/gamesfrontiers_0323
http://www.wired.com/gaming/gamingreviews/commentary/games/2009/03/gamesfrontiers_0323

이올린에 북마크하기
2009 Game Design1.doc
game mechanics .pdf