“ As soon as this process of [sc. capitalist] transformation has sufficiently decomposed the old society from, top to bottom, as soon as the labourers are turned into proletarians, their means of labour into capital, as soon as the capitalist mode of production stands on its own feet, then the further socialisation of labour and further transformation of the land and other means of production into socially exploited and, therefore, common means of production, as well as the further expropriation of private proprietors, takes a new form. That which is now to be expropriated is no longer the labourer working for himself, but the capitalist exploiting many labourers. This expropriation is accomplished by the action of the immanent laws of capitalistic production itself, by the centralisation of capital. One capitalist always kills many. Hand in hand with this centralisation, or this expropriation of many capitalists by few, develop, on an ever extending scale, the co-operative form of the labour-process, the conscious technical application of science, the methodical cultivation of the soil, the transformation of the instruments of labour into instruments of labour only usable in common, the economising of all means of production by their use as the means of production of combined, socialised labour, the entanglement of all peoples in the net of the world-market, and this, the international character of the capitalistic regime. Along with the constantly diminishing number of the magnates of capital, who usurp and monopolise all advantages of this process of transformation, grows the mass of misery, oppression, slavery, degradation, exploitation; but with this too grows the revolt of the working-class, a class always increasing in numbers, and disciplined, united, organised by the very mechanism of the process of capitalist production itself. The monopoly of capital becomes a fetter upon the mode of production, which has sprung up and flourished along with, and under it. Centralisation of the means of production and socialisation of labour at last reach a point where they become incompatible with their capitalist integument. This integument is burst asunder. The knell of capitalist private property sounds. The expropriators are expropriated.” (Marx 1906: 836–837).Whatever you think about the tendency of capitalism towards monopoly, it is the passage at the end that is relevant here.
According to Marx, the historical progress of capitalism – asserted here as a form of historical necessity or historical law – is allegedly that the (1) working-class always increases in numbers, and (2) so does the “mass of misery, oppression, slavery, degradation, [sc. and] exploitation; but with this too grows the revolt of the working-class.”
Except it didn’t happen like this. Even 19th century capitalism was increasing living standards and there arose a new middle class of professionals, lawyers, management, teachers, technocrats and others. The size of the working class as a percentage of the population eventually stabilised.
Highly developed and advanced Western capitalist states like Britain and the US proved the most resistant to communism and Marxism, and when communist revolutions broke out it was in backward Russia and China. Even the communist outbreaks in Germany and Italy at the end of the First World War were more the result of the collapse of those nations under the strain of war, and not in line with the vision Marx had predicted.
Marx, Karl. 1906. Capital. A Critique of Political Economy (vol. 1; rev. trans. by Ernest Untermann from 4th German edn.). The Modern Library, New York.