The promulgation of the Great Leap Forward was the result of the failure of the Soviet model of industrialization in China. The Soviet model, which emphasized the conversion of capital gained from the sale of agricultural products into heavy machinery, was inapplicable in China because, unlike the Soviet Union, it had a very dense population and no large agricultural surplus with which to accumulate capital. After intense debate, it was decided that agriculture and industry could be developed at the same time by changing people’s working habits and relying on labour rather than machine-centred industrial processes. An experimental commune was established in the north-central province of Henan early in 1958, and the system soon spread throughout the country.

Under the commune system, agricultural and political decisions were decentralized, and ideological purity rather than expertise was emphasized. The peasants were organized into brigade teams, and communal kitchens were established so that women could be freed for work. The program was implemented with such haste by overzealous cadres that implementswere often melted to make steel in the backyard furnaces, and many farm animals were slaughtered by discontented peasants. These errors in implementation were made worse by a series of natural disasters and the withdrawal of Soviet support. The inefficiency of the communes and the large-scale diversion of farm labour into small-scale industry disrupted China’s agriculture seriously, and three consecutive years of natural calamities added to what quickly turned into a national disaster; in all, about 20 million people were estimated to have died of starvation between 1959 and 1962.

This breakdown of the Chinese economy caused the government to begin to repeal the Great Leap Forward program by early 1960. Private plots and agricultural implements were returned to the peasants, expertise began to be emphasized again, and the communal system was broken up. The failure of the Great Leap produced a division among the party leaders. One group blamed the failure of the Great Leap on bureaucratic elements who they felt had been overzealous in implementing its policies. Another faction in the party took the failure of the Great Leap as proof that China must rely more on expertise and material incentives in developing the economy. Some concluded that it was against the latter faction that Mao Zedong launched his Cultural Revolution in early 1966.

China's Industrial Revolution didn't happen until the late 70s, long after the great leap forward had failed and 2 years after Mao had died.

Marx stated that communism could only result from an advanced industrial society like Germany or the UK were in the early 1900s. Lenin responded to this with brutal rapid industrialization to bring the USSR from an agrarian economy to a modern industrial superpower. Mao did the opposite - he ignored Marx's directives and reinforced a rural, agrarian economy with limited industry, deciding the revolution would happen through the peasant class rather than the worker class.

Karl Marx believed that a communist revolution could only begin in an already-industrialized capitalist state. He predicted that this sort of society would create the political means and motivation for them to seize control of and redirect the resources of society towards benefiting the needs of the majority, as opposed to an elite minority (Defronzo 44).  This was because of how such a society mass-organized and alienated the masses. A peasant society, conversely, would not be receptive to revolutionary goals because of the peasantry’s ties to tradition, sense of powerlessness, and relative ignorance of the world beyond the village (Defronzo 112). Peasants would therefore be unable to develop class consciousness, and in turn would never engage in revolution to improve their plight.

Mao disagreed with Marx’s analysis of a peasant society, believing that it too could engage in and win a revolution. He recognized how Chinese peasants of the past had supported the revolutionary, untraditional ideologies espoused by the Taiping and Boxer rebellions. This contrasted with Marx’s belief that the peasants were a reactionary, traditionalist class. He was also aware of how the peasantry had engaged in rebellion against rulers who ‘lost’ the “Mandate of Heaven” and against imperialist powers. Mao equated the peasantry’s tradition for rebellion with class consciousness, and believed that the “Sinification of Marxism”, which fused that tradition with the ideology of Marxism, would enable a successful, peasant-based communist revolution to occur in China (Defronzo 120). Mao thus had supreme faith in the peasantry, seeing it not as a backwards reactionary class but rather as the class which would enable and carry out revolutionary change in China.

The famine you were talking about was actually caused by the massive relocation of farmers to industrial areas

Most of them were moved to rural communes and collective farms. Agriculture was by far the biggest industry.

So there is still the fixation on industrialism, through both Mao's ideology as well as the european authoritarian communists.

Yeah, agriculture and backyard furnaces are still industrialiasm but it's not what Marx was talking about; society revolving around advanced industrial cities; manufacturing hubs. Mao's industry had little to do with what Marx envisioned. It was primitive in comparison to Europe's industrial society and this was in keeping with Mao's technological conservatism:

Mao was suspicious of Soviet models of economic development. Instead, Mao favoured an ideological shift in economic policy that would continue industrialisation but also move China towards agricultural collectivisation. This may have been driven by Mao’s suspicions about the growth of technology, the rise of a potentially bourgeois‘expert’ class and the expanding divide between urban and rural production. Implemented in 1958, the Great Leap Forward had two objectives: to create an industrialised economy in order to ‘catch up’ with the West; and to transform China into a collectivised society, where socialist principles defined work, production, even people’s lives. History records the Great Leap Forward as a disaster. It gave rise to economic stagnation, led to food shortages and famine, and caused the deaths of untold millions.

That’s just wrong.

There was barely any heavy industry in China until after Mao's death. Even rural farm machinery was minimal until the 60s. China's urban industrialization didn't happen until the late 70s.

We're comparing it to Soviet industrialization which was rapid and all-encompassing. The failures of the Soviets are what informed Mao's caution with industrialization.