As a matter of fact, poor workmanship and quality control fails on many, many man made items.
Custom built homes where the basement floor drain is the highest spot on the basement floor, windows that leak, doors that don't fit, trim corners that don't mate, etc.
Motor vehicles that leave the factory with a bent camshaft, loose bolts, electric windows that don't function, etc.
The same is true in appliances, furnaces, central air conditioners, etc. to include products made both within the USA and imported.
Poor products used to produce an item or poor quality control occurs in every product line produced from medicine to sump pumps, and NOT just in the world of RV's.
I know pointing to other examples does NOT excuse any one but that, sadly, has become 'the way of it' in this mostly "throw away" world of instant gratification.
Just my take on it.
2012 Fun Finder XT 276 Toy Hauler & Harley Davidson Ultra Classic with Condor wheel chock
2014 Dodge Ram 2500 AT 4X4 Crew Cab 6.4 L Hemi, 373 gears, tow package, Rambox option, Revolver X2 tonneau cover, Equal-I-zer anti-sway hitch.