Why did China introduce "Economic reforms" even when they did not have any compulsion as dictated by World Bank and IMF to India and Pakistan?

There was lack of modernisation in Chinese economy

The Chinese government at that time was not happy with the slow pace of growth and lack of modernisation in the Chinese economy. They felt that Maoist vision of economic development based on decentralisation, self sufficiency and shunning of foreign technology, goods and capital had failed. Despite of all the policies which were introduced in the past, the per capita grain output in 1978 was the same as it was in the mid-1950s. This made the government introduce reforms in year 1978.