Generally speaking, companies should focus more effort on prevention and appraisal. And prevention is usually better than appraisal. Most authorities agree that the costs of internal and external failures have been largely hidden and as a consequence managers are unaware of the magnitude of the problem. Very simple steps can often be taken to prevent defects. These simple steps pay enormous dividends in terms of reducing the need for appraisal and in reducing the incidence of internal and external failures.