It doesn't have to be people "hoarding". It just has to be people buying faster than the just-in-time system has enough supply buffer to buffer for. If a very l

It doesn't have to be people "hoarding". It just has to be people buying faster than the just-in-time system has enough supply buffer to buffer for. If a very large demand spike drains the system of supply, then you're going to get at least one of high prices or shortages, and no rule against both. If high demand persisted, the system would start producing more, but since we are fairly confident it won't, it becomes difficult for the producers to justify any additional capital outlay, limiting the rate at which they can spin up new supply.