I've read in a different place that the many problems could be a result of uncareful and miscoordinated outsourcing, particularly in the software domain. Is there any good information / insight on this?
Both this issue and issue with the door bolts were caused by Spirit, who Boeing outsourced the production of fuselages to. There's lots of info on the quality troubles with them going back years.
For example here is an article from May of last year [1] about a quality issue with Spirit that had been going on for 4 years. Here [2] is one from last October which says "The goal of the agreement is to stabilize Spirit’s production system, by stemming the flow of quality defects that have afflicted the 737 MAX and the 787 Dreamliner jet programs this year and positioning Spirit to ramp up to Boeing’s planned rate increases." The agreement was Spirit running out of cash and Boeing swooping in to save them despite their poor quality, because they were the only supplier for these fuselages. The financial times wrote a good article about it [3].
This is absolutely a story of outsourcing gone wrong. But they didn't outsource it to China or Mexico, they outsourced it to Kansas, USA.
> Both this issue and issue with the door bolts were caused by Spirit
From what I've read, this is not what happened for the door bolts.
The New York Times report was that Spirit required access to some part of the fuselage masked by the door but did not work on the door. The Spirit request was granted, so Boeing workers removed the door, Spirit workers did what they intended to, then Boeing workers put the door back. There is a entry in the maintenance log of the plane about this. There should have been a routine check after this operation, but there was no mention of it in the maintenance log.
