Studio art and commissions, what is the difference?

Looking at Art:

An Italian college student gave my husband and me a tour of the Sistine Chapel when we were in Rome. The Sistine Chapel paintings were commissioned by the church. According to our young guide, Michelangelo received repeated visits from a bishop who was critical of the paintings. The remarks made the painter so angry that Michelangelo painted the bishop in hell in his Last Judgement mural.

I have been told by other artists that commissions are tricky because instead of working for yourself, you must make the work please someone else.

Work in the Studio:

I recently completed a portrait commission of a two-year old girl. The client was very supportive and helpful during the process. However, I found myself super critical of the work as I made progress on the portrait. It was surprising to me that the voice of the critic in my head became much louder than usual adding unexpected tension to the work. In the end, the client was pleased and I was greatly relieved.

Ice Cream, Watercolor, 14” x 11”