Brain, too. Wear it out.

There's collectors who buy stuff and then never use it. Like they'll get some Star Wars action figures (they are not dolls don't call them dolls boys don't play with dolls) and never unwrap them so they can keep them perfect forever. Or those beautiful doll houses that no child will ever touch, the tiny wooden rocking chairs crying out to be splintered, swept up, and discarded. And your own personal working parts, like for instance liver? Use them up while you still can, otherwise people like Jack Bruce and David Crosby will get all the enjoyment out of them.