Just one story of many;
A few weeks ago I was in a waiting room of an office building. There were some interesting elements in there like a set of large rocks and a mini zen sandbox. A woman casually asked me what I thought the rocks were for. "Not sure," I said. Then she leaned over and started running her finger through the mini sandbox. "And this?" she asked.
"Oh, I don't know," I said "...maybe it is just for playing with. Sometimes it is nice to make choices that don't matter". She stopped and looked up at me with tears in her eyes. We were silent from then on but the idea that her choices might be playful had deeply resonated with her.
Clearly, that stranger and I had happened upon something quite vital about play. Sometimes the greatest gift of process oriented artmaking is allowing yourself to enjoy your own natural instinct. To just follow your curiosity... what a relief; to not have to be right...just to be.

And here is a bit of science as well;
This article outlines an experiment done to test reactions to art making. https://www.sciencedaily.com/releases/2017/06/170613120531.htm

"In fact, in surveys administered to the participants after the activities were complete, respondents indicated that they felt more like they had "good ideas" and could "solve problems" than before the activities. Participants even said they felt the three-minute time spans for art-making weren't long enough."