The Indian government had put barriers to foreign trade and foreign investment to protect domestic producers from foreign competition, especially when industries had just begun to come up in the 1950s and 1960s. At this time, competition from imports would have been a death blow to growing industries. Hence, India allowed imports of essential goods only.
In New Economic Policy in 1991, the government wished to remove these barriers because it felt that domestic producers were ready to compete with foreign industries. It felt that foreign competition would in fact improve the quality of goods produced by Indian industries. This decision was also supported by powerful international organisations.