The reasons for the three major changes in the seventh grade historical planned economy are as follows.

The reasons for the three major reforms are: after the land reform, agricultural production has been restored and developed. However, China's agriculture is still scattered, and it is difficult to solve the problems of production tools, capital and water conservancy, and it is difficult to resist natural disasters, which affects the development of agricultural production and cannot meet the needs of national industrialization.

Essence: The transformation from private ownership of means of production to socialist public ownership is politically manifested in the establishment of a socialist system.