Clothes often look horrible in video games. People look like they have their suits and dresses painted on their bodies. Or their capes clip right through their arms.
And hair... long hair almost never works. So you get all these games that won't let you give your character long hair.
Thank goodness we've got people like Cloakworks' Joe van den Heuvel trying to solve this. He's got some tech called Shroud that he's showing in a small booth at the Game Developer's Conference (here's the official website). The tech was borne from work done for a Batman: Gotham by Gaslight pitch (see that here). It will be used in the next Hitman, Hitman Absolution. I expect Agent 47's coat to flap and drape realistically. Now if only the guy had long hair...