As Jim Riley explained below

“Quality control is the more traditional way that businesses have used to manage quality. Quality control is concerned with checking and reviewing work that has been done. But is this the best way for a business to manage quality?

Under traditional quality control, inspection of products and services (checking to make sure that what's being produced is meeting the required standard) takes place during and at the end of the operations process.”

This quality control explanation is given by Jim Riley

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