"Artists themselves are not confined, but their output is"

This quote by Robert Smithson talks to the idea that while artists are not limited in their innovative expression, the art they produce is. Smithson is recommending that the artist is free to check out and create whatever they want, but the art they produce is confined by the boundaries of the medium they are operating in. For example, a painter is limited by the canvas size and the colors of paint they have offered. Similarly, a sculptor is limited by the materials they need to work with. Smithson is highlighting that while the artist is not confined, the art they produce is. This is because the artist is restricted by the tools and materials they have available to them. Smithson's quote is a tip that while creativity is endless, the art produced is not.