My particular disabilities can impede KB+M on a bad day, but things like Kinect, Move, and the Wii controller are out of the question even on the best of days. If the industry continues moving in that direction, I and people like me simply aren’t going to be buying their products any more.
Applecup, via RockPaperShotgun

Many interactions that seem natural and intuitive to many people cause significant difficulty for others. A mouse for example involves calculating and moving along a precise trajectory, maintaining a steady velocity, the spatial metaphor of moving on a different plane to the screen, and so on – a great deal more cognitive and motor ability than simply pressing a button.

Although digital controls will seem less accurate for some players, for others they will be the only possible way of playing, particularly if they rely on assistive technology rather than standard controllers.

Best practice example: Doom