Till now i never thought about this! For some reason i always assumed that everything always just fell into place and worked but i suppose its not the case as ideas can wonder and not fit in with the general style of the game, i guess this is where the art director comes in.
Art Directors are in charge of making sure the visual essence of a game and artistic vision is maintained during the development process. They oversee the project from its design document all the way through production till release when im sure there is much relief.
They Work very closely with the Art Manager to ensure consistancy in the style and feel of the game this even stretchs to the interactivity of the game.
The job of Art Director does not necessarily have to be creative though seeing as the job would be taken up by an expierenced artist anyways that would probably come standard.
Its a well known fact that games and films are becoming very similar in the sence of structure and even production times but on a artistic level in game cut scenes and story lines are becoming very similar to that of films and more and more art directors are having to follow similar development methods.
The role of Art director seems no walk in the park and really requires years of artistic experience and the ability to know what will work and what will not while at the same time thinking from the perspective of the consumer. So overall a very demanding job with the need for good, motivation, innovation and communication skills.
With me personally the skills i would need to develop are my motivation in which for an artist in general is a key componant and something i will be sure to work on not sure if the job would be good for me though if i was a chess piece i would definatly be a pawn.