I think you are still overlooking the fact that say 95% of the buyers will accept these defects that only matter to you and me, and not even notice them. If DJI discovers these defects during QC, then they have to fix them, which they
won't have to do if the buyer never discovers the defect, or never complains about it. It's simple economics. It's not the cost of inspection. It's the cost of repair of a mildly defective unit that a buyer will likely never complain about. If they do, they just give them another. Trust me. If DJI could make more money doing it your way, they would! They make more money doing it this way. Returning a unit to DJI is a PIA and may not even result in any improvement.