The requirtement for ISO 9000 has the result that the pool of potential bidders is small and the government gets poor value for its money and effectively guarantees that the winner is inefficient.
At present, it is a requirement of most government tenders that bidders are accredited to ISO 9000. As anyone who has the misfortune to work for an ISO 9000 certified company will know, ISO 9000 is essentially a way to create enormous amounts of stifling bureaucracy supervised by jumped up jobsworths both internally and externally. Surprise surprise, companies which do not tender for government work do not register for ISO 9000. It is well known that ISO 9000 is almost impossible to lose (because there is money to be made from accreditation) and there is no evidence that ISO 9000 accreditation is associated with success in business. For more details, read the works of John Seddon at http://www.systemsthinking.co.uk (Note that I have no connection with Mr Seddon).