“What economists call over-production is but a production that is above the purchasing power of the worker, who is reduced to poverty by Capital and State.”

Anarchism: Its Philosophy and Ideal (1896)
Context: What economists call over-production is but a production that is above the purchasing power of the worker, who is reduced to poverty by Capital and State. Now, this sort of over-production remains fatally characteristic of the present capitalist production, because — Proudhon has already shown it — workers cannot buy with their salaries what they have produced and at the same time copiously nourish the swarm of idlers who live upon their work.
The very essence of the present economic system is, that the worker can never enjoy the well-being he has produced, and that the number of those who live at his expense will always augment. The more a country is advanced in industry, the more this number grows. Inevitably, industry is directed, and will have to be directed, not towards what is needed to satisfy the needs of all, but towards that which, at a given moment, brings in the greatest temporary profit to a few. Of necessity, the abundance of some will be based on the poverty of others, and the straitened circumstances of the greater number will have to be maintained at all costs, that there may be hands to sell themselves for a part only of that which they are capable of producing; without which, private accumulation of capital is impossible!
These characteristics of our economical system are its very essence. Without them, it cannot exist; for, who would sell his labor power for less than it is capable of bringing in, if he were not forced thereto by the threat of hunger?
And those essential traits of the system are also its most crushing condemnation.