In 2016, a Business Insider Intelligence report predicted that, by 2020, there would be 10 million autonomous vehicles on the world’s roads. At the time, the technology was maturing at such a rate as to make the projection seem entirely plausible. Driverless cars were widely considered a viable alternative to existing high-capacity public transit networks. But as 2021 begins that 10 million figure looks wildly inaccurate and the promise of autonomous vehicles remains unrealised.