Worse things happen. Actually quality control in the gunmaking world is generally (CAI and Hesse aside) world's better than that found in the rest of the manufacturing world.
Most cars have significant quality issues ranging from bad interior trim to poorly installed parts. Many newly built homes (especially those built on spec) have serious shortcuts taken in their construction ranging from siding installed directly over the sheathing without housewrap, to substandard framing lumber substituted for the specified grade, to walls that are installed out of square, plumb and level. Many basements I have seen have been improperly waterproofed below grade, either lacking foundation coating or not having had the form rods removed and sealed up. A house is a HUGE investment, and many have significant problems right out of the box. By contrast, the vast majority of guns, sights, mounts, etc. are 100% reliable, safe, and accurate from the factory.
That said, it sounds like ARMS may have had a problem with QC on a batch of 22m68's. I need to check mine out now.