Too Long; Didn't Read
One kind of token model that has become popular among many recent token sale projects is the “network medium of exchange token” The token would, in a meaningful economic sense, be backed by the services provided by the developers. This kind of economic model is clearly stable, but you can see how this model is more complex and more tenuous than the simple “developers as seller” model. It’s possible that the token would depreciate in each round, with its value multiplying by some factor f where v / w < f < 1, until it eventually reaches a price of zero.