I think process-based art relates to mindfulness because with process-based art, you only focus on the present and make marks and see where the marks take you. Accepting all feelings and thoughts and emotions and surroundings and acknowledging them and placing them on a canvas.
I had a professor in college who encouraged me to make more process-based art because at the time, I was really tight and realism/detail oriented, and letting go and trusting the process was really freeing and fun, and pushed my art to new places. It was especially freeing to break the rules of art and add thick globs of oil paint, drip paint, scrape paint, turn the canvas around and switch the orientation of the artwork as I worked. And mixing gunk (dried paint, beads, yarn, string, fabric) into the paint. It’s really liberating to take a material as expensive and “high” art as oil paint and fuck it up. Especially because oil paint is primarily associated with the old masters and western, European art. I love taking a “precious” material and destroying it.