Mindfulness, Relaxation, and Stress Reduction! Good stuff!
The repetitive motion of coloring, the limited space of the page, and the small lines/shapes all help your mind to focus on doing one thing at a time – a relief in our multi-tasking world. I love books with patterns, which are especially helpful in creating a locus point around which thoughts can revolve and let go.
It may sound silly, but my clients consistently surprise themselves with how much they enjoy it. Try it!