The second counter-argument is that further goods market integration might also lead to more specialization in production. Once individual firms can easily serve the whole OCA market, and not just their national market, they will exploit economies of scale and concentrate production. Some sectors in the OCA might end up becoming concentrated in a few locations. The United States is a good example: financial services are centered in New York City, entertainment in Los Angeles, and technology in Silicon Valley. If specialization increases, each country will be less diversified and will face more asymmetric shocks; weakening the case for the self-fulfilling OCA argument.