A reader at respected airline industry site Leeham News offered a comment that suggests they have access to Boeing’s internal quality control systems, and shares details of what they saw regarding the Boeing 737 MAX 9 flown by Alaska Airlines that had a door plug detach inflight, causing rapid decom...
Here's a New York Times article from 2019 on persistent quality control issues during production of the Dreamliner, including one time someone left a ladder inside the tail of a plane.