Here is a parable to illustrate the process. Suppose that a primitive maker of cloth decorates her product with a complex design. As it turns out, everybody else in the community shares in the perceptual pleasure she enables, which gives her an economic incentive to produce more patterned cloth. Maybe others copy her as well, and insinuate themselves into her domain. At this point, repeated perceptual attention to the pattern will induce in consumers a greater sensitivity to the subtleties of patterned cloth. Thus, consumers (including the maker herself) become sensitised to imperfections in the patterns – perhaps the spatial interval is not perfectly even, or perhaps the repeated element is not exactly the same throughout. This gives producers the incentive to improve their skills and, because they invest in beauty, it gives consumers an incentive to improve their skills of discrimination. The result is a virtuous spiral in the co-development of perceptual and productive skills.

This is precisely what doesn't happen in juggling, which is why it doesn't fall into the "sport" and "winning" model. Cool!