Personality goes a long way…

Look at Super Mario 64. Though Mario has a fairly distinctive look, what really is his personality? He does not actually have one, leaving him undefined enough for the player to imprint her own personality on him. What about Lara Croft in Tomb Raider? Again, a very distinct appearance, a very undefined personality. And if one looks at the space marine in Doom or Gordon Freeman in Half-Life, one will find no personality whatsoever.

Game Design: Theory & Practice Richard Rouse III