In the process of painting you focus your attention on a subject that is at your fingertips. If you do it with enough concentration, it will ignore the extraneous noise, unpleasant thoughts and worries. This is a very useful skill that will be useful in situations where you need to briefly forget about your physical or emotional pain.
There are rare instances of contour drawings of famous architectural structures and monuments with a variety of parts made in a realistic manner. Such coloring is complex to implement and is designed for adults.