ZBrush as a Character Design Tool - ZBrush Creature Design: Creating Dynamic Concept Imagery for Film and Games - page 30

Contrast
You can get interesting effects if you break from balance by introducing the principle of contrast. Depending
on the effect you want, you can either balance or contrast your forms. I find it's best to contrast and try to
avoid perfect balance in most cases. The degree of contrast will, of course, impact the effect you get. Bal-
ance is rarely interesting, as it does not create any sense of tension. Figure 1-29 shows contrast and tension
by clustering the shapes in an asymmetrical manner. One practical example of where contrast is useful is