“We are fascinated with robots because they are reflections of ourselves.” – Kenneth Goldberg

When one thinks of the evolution of manufacturing, it’s often done through the lens of outdated stereotypes: a gritty factory floor that’s transformed into a highly automated environment, complete with a supply line where human workers have been replaced by sophisticated robots.

To some extent, this is an accurate reflection of a decades-long automation trend in manufacturing. Large numbers of complex robots have been replacing some human workers. The tireless efficiency and virtually error-free functionality of robots make them well-suited to perform demanding assembly and production tasks, all while reducing or eliminating human error, improving cycle times, boosting productivity and enhancing workplace safety.

There’s a new twist in that narrative, however.

Lately, a very different trend has begun to manifest itself, with precisely the opposite results: manufacturers have begun replacing robots with humans. This is not driven by nostalgia or from a desire to provide more manufacturing jobs — it is simple, practical self-interest on the part of manufacturers.

Consumer pressures for a wider variety of choices are driving product variation to new heights, and there is a correspondingly higher need for a key advantage that humans have over their automated counterparts: flexibility. The human ability to think critically and adapt to changing circumstances on the fly is beneficial in an environment where near infinite variations of certain products make it logistically or economically impractical for robots to perform tasks with a similar degree of customization.

Iconic global brands like Mercedes-Benz have taken significant steps in this direction, replacing some large manufacturing robots with human operators. The notion that “Mercedes-Benz is firing robots,” as one article put it, highlights larger issues of automation and the longer-term implications for the job market. But as Markus Schaefer, head of production at Mercedes-Benz’s parent company Daimler, noted in an interview with Bloomberg (via MIT Technology Review), the move by the luxury car maker was strictly a business decision, driven by some very practical considerations: “Robots can’t deal with the degree of individualization and the many variants that we have today. We’re saving money and safeguarding our future by employing more people.”

Schaefer is affirming what many manufacturers have discovered for themselves: Robots’ unmatched ability to handle repetitive tasks becomes less of an asset — and even a potential liability — once levels of variation increase past a certain point. Even the most adaptive automated systems need to be programmed and adjusted, and that necessity adds a level of expense and inefficiency that eventually nullifies some advantages.