One of the 2 SpaceX falcon 9 failures, CRS-7, was caused by the manufacturer claiming a strut (metal pole) was rated to N lbs but in reality its failure point was N/2.
SpaceX sourced the material from an industrial supply company, not an aerospace company, and that company’s material testing procedures were less strict. During launch the strut failed and caused a “rapid unscheduled disassembly”. Or, as I like to say, an sad boom.
It’s a little different than what’s going on with these aircraft but it’s similar. These companies really need to test the stuff they buy because your supply chain