The DARPA challenges offer a useful playbook for physical AI. They show how an impressive technical demonstration can help create an industry. But they are not a timeline. The first DARPA Grand Challenge for autonomous vehicles took place in 2004. DARPA launched the Robotics Challenge eight years later, in 2012, with the Finals taking place in 2015. It is tempting to conclude that physical AI is therefore eight or eleven years behind autonomous driving. I don’t think that works.