Think about it. What if a car company outsourced its entire vehicle production operations to a secondary entity that would operate like an automotive version of Foxconn, Apple's gigantic manufacturing partner?
Wouldn't that automaker be at a competitive advantage? Wouldn't it be rewarded in spades by the stock market? Ultimately, all traditional automakers would be pressured by investors to offload their costly, complicated manufacturing operations to an entity willing to run them on a cost-plus basis.
It's already happening, albeit at a smaller scale. The services of the industry's best-known contract manufacturer, Magna, are in high demand, especially from premium brands. That relationship works because Magna is good at what it does, and automakers know and trust that fact.
Now imagine the world's vehicle assembly in the hands of a single, super cost-efficient back-end manufacturer? That company could dictate common loading points across various designs, allowing the factories to be flexible enough to build similar-sized products for several manufacturers simultaneously.
As robotics continue to advance, the cost structure of these factories would drop precipitously even as manufacturing complexity increased. This automotive Foxconn would have sufficient scale to make its own 3-D printed tooling, and eventually maybe even "print" its own automobiles.
At that point, giant automotive factories would be unnecessary. Instead, you'd have localized printing centers where consumers would pick up the completely personalized automobiles that they had designed and paid for at their local dealer a few days before.