Generally, it is true that country operates without trade barriers results in benefits such as the growth of an economy. However, despite all these benefits a low income country put up barriers to trade, such as tariffs on imports, because of the following reasons:-
a) A low income country placed tariffs on imported goods as a way of protecting sensitive industries, for humanitarian reasons and for protection against dumping.
b) A low income country also imposed tariffs on imported goods to protect an industry that is important for national security.