Tesla shares fell about 13.5% on Thursday, marking one of the company’s largest single-day losses and reflecting investor unease over weak profits and extensive spending on artificial intelligence, robotics and autonomous driving. The decline adds to Tesla’s poor performance this year and highlights scepticism about whether Elon Musk’s future-focused projects can deliver returns soon enough.

Second-quarter earnings came in at 31 cents per share, below analysts’ expectations of 51 cents, although revenue exceeded forecasts. Tesla spent $5.8bn during the quarter, producing negative free cashflow of $1.1bn, while its Robotaxi service remains limited and its Optimus robot is not yet sold to consumers; wider technology-stock losses also erased $767bn from the “Magnificent Seven” companies’ market value.