>The basic formula of level design is when you start out you need to teach the player how to play. For every level in the first chapter you have to have some mechanic forcing the player to do something new to beat the level.
>It teaches the player that an action is possible, and also makes the player feel a sense of achievement as they feel they discovered something themselves.
>You need to be able to employ a mechanic in at least three to four different ways, or else it is a waste of space (i.e. saws, moving saws, rotating saws).
Edmund McMillian, Super Meat Boy creator.
REF: Pajot, L. (Director). (2012). Indie Games, the Movie [Documentary]. United States