As Ricky pointed out-"Sometimes you simply do not have the tools to allow Bryce to do the whole job by itself." . . . . .

A painter has the option of using a paintbrush to change every surface characteristic of the painted image, such as placing highlights and shadows, playing soft edges against hard edges, blending in a complimentary color here or there for visual contrast. All these artistic choices are lost to a great extent when rendering an image in a 3d software program. Postwork on an image allows the artist to change the rendered image into a complete and personal vision. I am certain that at some point in time every artist looks at one of their 3d renders and thinks to themselves that sometime was missing. . . . .the personal touch!