Payment delinquency is a significant problem as the collections infrastructure is not well developed. When consumers default, the creditor has little recourse. The U.S. Postal Service is highly reliable. Statistically, the USPS is one of the most reliable in the world. In addition, private delivery services like FedEx, UPS and others are relatively economical and efficient.
Most postal services are unreliable.
Because of high overhead costs, private delivery services are expensive. Bureaucratic customs procedures also slow the delivery process. The bottom line is that consumers have to wait a long time to receive goods and often pay steep customs taxes. The US maintains a single currency. Latin America has many currencies which creates a high foreign exchange risk.