Trusts came into existence because they were the most efficient units in those industries which, being relatively new, were too small to support more than one large company

As the market expands, new firms enter the field, thus cutting down the share of the market held by the dominant firm. This has been the pattern in steel, oil, aluminum, containers, and numerous other major industries. The observable tendency of an industry's dominant companies eventually to lose part of their share of the market, is not caused by antitrust legislation, but by the fact that it is difficult to prevent new firms from entering the field when the demand for a certain product increases.

It takes extraordinary skill to hold more than fifty percent of a large industry's market in a free economy. It requires unusual productive ability, unfailing business judgment, unrelenting effort at the continuous improvement of one's product and technique. The rare company which is able to retain its share of the market year after year and decade after decade does so by means of productive efficiency – and deserves praise, not condemnation.