I was a professional photographer for many years, taking pictures mostly for advertising, catalogs, promotion, etc. Eventually, I gave it up, mostly due to the ad agency people I was dealing with. I was being told how to shoot by people with little or no visual sense. It caused me to put my cameras away for ten years. When I began taking pictures again, it was entirely for myself, which I see as the purest form of the art (or craft). It's been much more enjoyable that way.