Ted Reese

“Therefore, when labour-saving technology reduces total socially necessary labour time (per commodity – for an increase in the number of commodities made may increase socially necessary labour time in absolute terms), there tends to be a relative fall in the surplus value contained in the total value of commodities, ie less surplus value per commodity, despite the fact that the rate of exploitation has increased, ie that each worker is now giving the capitalist more surplus labour time and therefore producing more surplus value relative to their necessary labour. As Grossman says: “Technological progress means that since commodities are created with a smaller expenditure of labour their value falls. This is not only true of the newly produced commodities. The fall in value reacts back on the commodities that are still on the market but which were produced under the older methods, involving a greater expenditure of labour time. These commodities are devalued.”[67] The very possibility of crisis is contained in the contradictory nature of the commodity. It is at once an object of use, or use-value, and something that can be exchanged for another thing, an exchange-value. Since different commodities contain different magnitudes of value and therefore cannot be directly exchanged, the creation of money proceeds logically and historically from the contradiction. It is not the exchange of commodities which regulates the magnitude of their value, but the magnitude of their value which controls their exchange value. Exchange-value is the only form in which the value of commodities can be expressed. Someone will buy a use-value because they need or want it, but only if they can exchange it for something else, ie money. If they do not have enough money, they cannot buy it, and profit goes unrealised. But to focus on this final ‘surface level’ aspect is what produces the mistaken underconsumptionist theory, for it forgets or ignores where it arose from – the dual character of the commodity.”
― Ted Reese, Socialism or Extinction: Climate, Automation and War in the Final Capitalist Breakdown

“It is then simplest to think of the problem as follows: the purpose of commodity production is to convert the surplus value extracted from living labour into capital. But accumulation – the reproduction and expansion of capital – does not happen unless a sufficient magnitude of surplus value is produced. If the surplus value generated is insufficient then it only reproduces the part of capital that it is equal in value to – the rest becomes surplus capital. Capital is only fully “valorised” if it is reproduced and expanded. Grossman therefore says overaccumulation is produced by “imperfect valorisation”. This abstraction can be applied to ‘individual capital’, the capital owned by each individual capitalist, and total capital. Imperfect valorisation therefore explains cyclical crises. The total investment in production tends to grow faster relative to the growth of profits returned, because constant capital has to grow relative to variable capital. The mass of capital has continued to rise but at a declining rate. This is expressed as a falling rate of profit. There is a lack of surplus value relative to total capital  – an underproduction of surplus value is at once an overaccumulation of capital.”
― Ted Reese, Socialism or Extinction: Climate, Automation and War in the Final Capitalist Breakdown