Ford has admitted to rehiring hundreds of human workers after its aggressive AI adoption strategy backfired.

The US automaker hired over 350 veteran engineers, referred to internally as “gray beards”, over the past three years in order to address mistakes made by automated systems.

The staff will lead quality reviews after the automation issues cost the company billions of dollars, Bloomberg reported, while some workers will also help improve and train the AI systems.

“We had been relying more and more on automated quality systems and not getting the desired results,” said Kumar Galhotra, Ford’s chief operating officer.

“We brought back technical specialists and they hunt for failure points before a part ever reaches the plant floor.”