Elon Musk dreams of thousands of robots working in factories. Tesla's first Optimus lead has doubts.

Tesla Optimus robot prototypes walk onto the stage with Elon Musk.

Screengrab from We, Robot livestream

• Elon Musk has said Optimus — Tesla's humanoid robot — is the company's most important product.
• The billionaire said this week that Tesla would have "thousands" of Optimus robots working in its factories by the end of the year.
• Chris Walti, Tesla's first Optimus lead, told BI that humanoid robots are wrong for factory work.

Elon Musk dreams of Tesla's Optimus...