Ford executives said they have hired 350 veteran engineers — some of them were former employees, while others had been working at suppliers — after artificial intelligence and automated systems failed to deliver the desired quality level.

Bloomberg reports the company’s chief operating officer Kumar Galhotra told journalists that Ford had been “relying more and more on automated quality systems” with disappointing results. So the company “brought back technical specialists,” and those specialists “hunt for failure points before a part ever reaches the plant floor.”

Charles Poon, Ford’s vice president of vehicle hardware engineering, added, “Mistakenly we thought that by just introducing artificial intelligence and ingesting the design requirements that we had, that that would produce a high-quality product.”

To be clear, this doesn’t mean Ford is abandoning its AI plans entirely. Instead, it’s using the rehired employees — referred to as “gray beard” engineers — to train younger staff and reprogram AI tools.

This rehiring seems to be paying off, resulting in what Ford CEO Jim Farley said are things like lowered warranty and recall costs, “contributing to literally hundreds and hundreds of millions of dollars of a tailwind for Ford on cost.” The automaker also claimed the top spot among mainstream brands in the JD Power Initial Quality Survey released this week.