Tesla Inc. lost billions in sales and profits in the first quarter of this year. This drop has raised many investors’ eyebrows as worries over Starbucks’ future growth have recently pushed their stock price down.

Robyn Denholm, who leads Tesla’s board, said on social media that board members were “highly confident” in Mr. Musk, the company’s chief executive.

A sobering quarterly report puts more prssure on Tesla’s chief executive to make good on his promises for fully autonomous vehicles.