https://electrek.co/2021/01/25/tesla-loses-best-engineering-...
https://www.engadget.com/2018-07-02-tesla-engineering-lead-d...
"Field, who previously worked at Apple and Segway, joined Tesla in 2013 to develop the company's next-generation EVs. In that sense, his mark on the company is hard to escape. However, there's a potential source of conflict. Elon Musk asked Field to handle both manufacturing and production in 2017, right as the Model 3 was becoming a practical reality. You may know what happened next. Tesla struggled to boost Model 3 production levels after relying too heavily on robots, and Musk took charge of manufacturing to be sure his company met its 5,000-a-week Model 3 production target. Field effectively lost a large part of his role."