In this video, a tech Youtuber, Linus, is showing us around the OnePlus factory. You do not have much factory experience or have never toured a manufacturing plant before, this is a good material.
It explicitly shows how the quality control is done in the factory level. Processes, Purposes, People, and Tasks of quality management are demonstrated clearly. (Although Linus never intended to make the video as a quality management case study. 🙂 )