Boeing Whistleblower: Production Line Has “Enormous Volume Of Defects” Bolts On MAX 9 Weren’t Installed::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 decompression of the aircraft. The takeaway appears to be that outsourced plane components have so many problems when they show up at the production line that Boeing’s quality control staff can’t keep up with them all.
Absolutely 0.0000000000 defects is impossible.
However, as an engineers, it's troubling to hear Boeing say things like "well we added a few more inspection points". Lack of inspection is a contributing cause but it's not the root cause.
Finding errors at the factory is great and a great way to go out of business (both due to increased cost, as well as eventual escapes)