Originally Posted by Gresp15C

Back in the day...

From what I've read, during its peak production, the Ford Model T was not tested before being shipped to dealers. The dealer was expected to do a fair amount of work to get each one running right. The customer was supplied with a bag of tools and a repair manual. There weren't enough workers in Detroit to get each car running.

Later on, building cars to higher quality standards meant that they were assembled and tested in the factory, and re-worked at the end of the production line to correct noticeable problems. Further work was required after market during the warranty period. This system was replaced by the Toyota Production System, first in Japan, then the US (in the 1980s), and finally in Europe. Today we expect cars to work without issue for years.

Near as I can tell, bikes are still manufactured like the Model T. They are not even completely assembled before being shipped: A frame set, and two wheels, come from separate production lines and are boxed and shipped. They are assembled by the dealer or the customer. Either way, a skilled shop or home mechanic ends up with a good bike. When I bought a new bike, the shop's mechanic tinkered with it for a while before I could ride it home, though I could find nothing wrong when I tested it. Granted, shops probably have some influence on quality, for instance they have to be aware of the cost of assembly and rework when they choose brands to sell. And the makers of higher quality components have adopted the Toyota Production System, since it's ubiquitous.