Left 4 Dead's simplicity offers purity of gameplay - the same reason that gamers keep returning to classic arcade games. Come to think of it, with a handful of levels and unpredictable events happening within them, Left 4 Dead has more in common with "Ms. Pac-Man" than just the eating. It's the same thing over and over - but when simple ingredients are perfectly prepared, what could be a mere snack becomes a feast. This one just happens to be on human flesh. [Holiday 2008, p.32]