1. A secret plot by Konami to surreptitiously teach certain rhythm impaired sections of society (i.e. engineering students) the basics of bass lines by luring them with shininess onto the dance pad and then appealing to their video game competitiveness to force them to listen to that little part of their brain which can sense musical patterns.
2. An outlet for people who occasionally feel the urge to do a jig.
Maybe if he played Dance Dance Revolution for, say, twenty years straight, he might learn to keep a beat. Maybe.