Monopolist whose high profits are caused by high prices, rather than low costs, will soon meet competition originated by the capital market.

The capital market acts as a regulator of prices, not necessarily of profits. It leaves an individual producer free to earn as much as he can by lowering his costs and by increasing his efficiency relative to others. Thus, it constitutes the mechanism that generates greater incentives to increased productivity and leads, as a consequence, to a rising standard of living.

- Ayn Rand. Capitalism: The Unknown Ideal (1966).