In summary, the PCT postulates a dynamic comparative advantage because the country source of exports shifts throughout the life cycle of the product. Early on, the innovating country exports the good but then it is displaced by other developed countries - which in turn are ultimately displaced by the developing countries. A casual glance at product history yields this kind of pattern in a general way. For example, electronic products such as television receivers were for many years a prominent export of the United States, but Europe and especially Japan emerged as competitors, causing the U.S. share of the market to diminish dramatically. More recently, Japan has been threatened by South Korea and other Asian producers. The textile and apparel industry is another example where developing countries (especially China, Taiwan, South Korea, and Singapore) have become major suppliers on the world market, displacing in particular the United States and Japan. Automobile production and export location also shifted relatively from the United States and Europe to Japan and later still to countries such as South Korea and Malaysia. This dynamic comparative advantage, together with factor mobility and economies of scale, makes the product cycle theory an appealing alternative to the Heckscher-Ohlin model.