The risks associated with the floating exchange rate system are being realized. In the current system, companies have to devote a portion of their capital to hedging the currency and commodity risks associated with operating their business. Hedging is supposed to limit risk but when things don’t go as expected, hedging can add unexpected risks (via WSJ):

These companies have lost money not because of their business but because of losses associated with their hedging programs. This makes it difficult to invest across currency borders since you have to judge not only the investment in the company but also the currency. The current exchange rate system (or lack thereof) adds risk (volatility) to the world economy and reduces efficiency.