That's a rule in comics as well. No family photos (a term I've heard used to describe perfectly centered pics with no camera tilt or interesting angles). 

Its especially true when doing action poses. The camera should never be straight. There should be no symetry along the left/right side of the body ie arms should be posed differently, legs should not be the same pose, hips should never be straight, head should be tilted etc.

I've seen some pretty nice renders that are complete snooze fests because they lack composition.