ISO 9001:2015 is not about ad hoc procurement of services and products. Every organization buy services and products, that are not critical for the business, without a system in place. ISO 9001:2015 clause 8.4 is about procurement of products and services relevant for the business, a kind of procurement that must be done in a systematic and consistent way. Only critical products and services procurement is mandatory to be included in the quality management system.
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