Competition is the final price determinant and competitive prices may result in profits which force you to accept a rate of return less than you hoped for, or for that matter to accept temporary losses. And, in times of inflation, the rate-of-return concept comes up against the problem of assets undervalued in terms of replacement. Nevertheless, no other financial principle with which I am acquainted serves better than rate of return as an objective aid to business judgment. This principle had governed the thinking of the Finance Committee of General Motors since 1917.

p. 140 - My Years with General Motors, 1963