Why was it necessary for a developing country like India to follow self-reliance as a planning objective?

A nation can promote economic growth and modernisation by using its own resources or by using resources imported from other vations. The first seven five year plans gave importance to 'Self Reliance' which means averting imports of those goods which could be produced in India itself. When the economy becomes 'self reliant' especially in the field of food grains, it can save foreign exchange and can promote exports. It call reduce its dependence on other countries.