Comment by ssl-3

> Since the point of copyright is to offer an incentive (to profit) from works it should be tightly tied to the market value of said works and the willingness of its owner to present them for sale.

> If nobody keeps selling X there's no reason to let X enjoy the protection of copyright.

Suppose Lucy paints original portraits of Barbra Streisand and sells them on eBay. She makes no copies of them; there are no copies of them for her to sell.

And Lucy is just a painter. She's not a printer. She's not a publisher. Again: Lucy only paints portraits of Barbra Streisand and sells them on eBay. That's all that she does.

But because Lucy isn't selling copies, then the portraits become public domain and anyone is free to copy them.

Why would that ever be a thing that encourages Lucy to paint more portraits of Barbra Streisand?