The faster different markets come to agree on a price for similar instruments, the more efficient the markets are. The profit opportunity for the fastest arbitr

The faster different markets come to agree on a price for similar instruments, the more efficient the markets are. The profit opportunity for the fastest arbitrageur drives competing arbitrageurs to compete. Ergo arbitrageurs are working with all of their skill and ability to make sure that markets are as efficient as possible. Now you have a global marketplace where investors have a pretty good idea that their local markets have reasonable prices. The system works for investors and arbitrageurs (the good ones, anyways) alike. What's wrong with that?