The global adoption of ISO 9001 may be attributable to a number of factors. In the early days, the ISO 9001 (9002 and 9003) requirements were intended to be used by procuring organizations, as the basis of contractual arrangements with their suppliers. This helped reduce the need for "supplier development" by establishing basic requirements for a supplier to assure product quality. The ISO 9001 requirements could be tailored to meet specific contractual situations, depending on the complexity of product, business type (design responsibility, manufacture only, distribution, servicing etc.) and risk to the procurer. If a chosen supplier was weak on the controls of their measurement equipment (calibration), and hence QC/inspection results, that specific requirement would be invoked in the contract. The adoption of a single quality assurance requirement also leads to cost savings throughout the supply chain by reducing the administrative burden of maintaining multiple sets of quality manuals and procedures.
A few years later, the UK Government took steps to improve national competitiveness following publication of cmd 8621, and Third Party Certification of Quality Management Systems was born, under the auspices of the NACCB, which has become UKAS.
In addition to many stakeholders' benefits, a number of studies have identified significant financial benefits for organizations certified to ISO 9001, with an ISO analysis of 42 studies showing that implementing the standard does enhance financial performance. Corbett et al. showed that certified organizations achieved superior return on assets compared to otherwise similar organizations without certification.
Heras et al. found similarly superior performance and demonstrated that this was statistically significant and not a function of organization size. Naveha and Marcus claimed that implementing ISO 9001 led to superior operational performance in the U.S. automotive industry. Sharma identified similar improvements in operating performance and linked this to superior financial performance. Chow-Chua et al. showed better overall financial performance was achieved for companies in Denmark. Rajan and Tamimi (2003) showed that ISO 9001 certification resulted in superior stock market performance and suggested that shareholders were richly rewarded for the investment in an ISO 9001 system.
While the connection between superior financial performance and ISO 9001 may be seen from the examples cited, there remains no proof of direct causation, though longitudinal studies, such as those of Corbett et al. (2005), may suggest it. Other writers, such as Heras et al. (2002), have suggested that while there is some evidence of this, the improvement is partly driven by the fact that there is a tendency for better-performing companies to seek ISO 9001 certification.