The main focus of the import-substitution policy in India was to boost domestic manufacturing of imported goods. This policy was implemented in the mid-20th century as a way to reduce dependence on foreign imports and promote self-sufficiency in the Indian economy. Here is a detailed explanation of this focus:

Import-Substitution Policy:
- The import-substitution policy was a strategy adopted by the Indian government after independence in 1947. It aimed to promote the growth of domestic industries by replacing imported goods with domestically produced goods.
- The policy was based on the belief that by reducing imports and increasing domestic production, India could become self-reliant and develop a strong industrial base.

Boosting Domestic Manufacturing:
- The main focus of the import-substitution policy was to boost domestic manufacturing of goods that were previously imported. The government provided various incentives and support to promote the establishment and growth of domestic industries.
- This was done through a combination of tariff protection, import restrictions, and subsidies for domestic industries. The government imposed high tariffs on imported goods to make them more expensive and less competitive compared to domestically produced goods.
- By making imports more expensive, the government aimed to encourage consumers to buy domestically produced goods instead, thereby boosting domestic manufacturing.

Reducing Dependence on Imports:
- The import-substitution policy was driven by the need to reduce dependence on foreign imports. Before independence, India was heavily dependent on imported goods, especially from the British colonial empire.
- The policy aimed to replace these imported goods with domestically produced alternatives. This not only reduced dependence on imports but also helped conserve foreign exchange reserves and improve the balance of payments.

Challenges and Criticisms:
- While the import-substitution policy initially saw some success in promoting domestic industries, it also had its challenges and criticisms.
- One of the main challenges was the lack of competitiveness of domestic industries. Due to the protectionist measures, many domestic industries became complacent and did not focus on improving efficiency and quality.
- Additionally, the policy led to the development of a highly regulated and bureaucratic system, which hindered innovation and growth in the long run.
- The import-substitution policy also faced criticism for neglecting the agricultural sector, which was crucial for India's economy. The focus on industrialization led to a neglect of agriculture, which resulted in food shortages and agrarian distress.

In conclusion, the main focus of the import-substitution policy in India was to boost domestic manufacturing of imported goods. This policy aimed to reduce dependence on foreign imports, promote self-sufficiency, and develop a strong industrial base. While it had some success in promoting domestic industries, it also faced challenges and criticisms, particularly in neglecting the agricultural sector and hindering long-term growth and innovation.