Elon Musk on Optimus: "We've started early production. The growth of Optimus is an S curve, but the initial curve is a shallow slope. We have the vast majority of the 1 million unit/year line installed at Fremont. There's still some things we need to tweak about the design. There's still quite a lot of work to do with the AI in the robot. I would expect that the AI, the electromechanical design, reliability, usage life, expect these issues to be solved by the end of next year. I remain convinced Optimus will be the biggest product on Earth. I do want to temper expectations that we still have a lot to get through, it will take about a year to get through that."