The failure here is that the door was not reinspected after the bolts had been removed to “open” it. A reinspection would be required if had been “removed”, and I’d bet that wings are always inspected for proper construction and installation (because there’s no way to “open” the wings).
I don’t believe the parent comment is saying the design is poor, it’s about the process during assembly and maintenance.
I don’t believe the parent comment is saying the design is poor, it’s about the process during assembly and maintenance.