International trade is very difficult. My friend has a firm and he wants to do business in other countries but he's scared of fluctuating exchange rates and taxes.
When a firm is working in a domestic market, changes are more predictable and everyone plays by the same rules. But in other countries, business culture varies and it can take a long time to understand how things work. A sudden change in exchange rates or a new tax imposed by a foreign government can be detrimental for a company. Many people can't take the risk.