A building inspector once rightly suggested that my under-floor plumbing was DIY. “No plumber would put a copper saddle on every joist, let alone use copper nails” So yeah, this story gives some home handymen a bad name.
More to the point: Serious airlines have resident company engineers at the actual factory where their aircraft are actually made. Why the hell would you not do likewise at an offshore MRO? Since all maintenance contracts are awarded on a cost basis why would you seriously expect the lowest bidder to always do the most correct (and hence costly) thing when no one was watching, given what we all know about human nature?
Perhaps “Trust, but verify” is too far in the past to inform managers who have only a degree in business administration and no ability in actual business leadership?