Tesla CEO Elon Musk said Thursday that he expects the company to begin selling humanoid robots to the public by the end of 2027.Why it matters: Musk has billed Tesla's Optimus robot as a globally transformational technology capable of performing innumerable human tasks.The big picture: Tesla's humanoid robots are already performing "simple tasks" in the company's factories, Musk said. The company will offer them for sale "when we are confident that there is very high reliability, very high safety and the range of functionality is also very high," Musk said at the World Economic Forum in Davos.The vision is "you can basically ask it to do anything you'd like," he said.Zoom in: Musk reiterated his belief in the future prominence of humanoid helpers.He said there will be "more robots than people.""I think everyone on earth is going to have one and want one," he said.He's not alone in believing that personalized robots will be transformational.Nvidia CEO Jensen Huang recently predicted that humanoids will be "one of the largest industries ever."And competitors are making progress too. Hyundai is reportedly weighing an IPO for its humanoid operation Boston Dynamics that would value it at $28 billion.Reality check: Musk has a long and acknowledged track record of promising products long before they become a reality. And there are profound technological challenges remaining for humanoids, including basic issues like hand function, Axios Future of Mobility author Joann Muller reported this month.Zoom out: Musk warned in an X post Tuesday that the early production rate for Optimus and Cybercab will be "agonizingly slow.""The speed of the production ramp is inversely proportionate to how many new parts and steps there are," he wrote in response to a post about the efficiency of Tesla's "unboxed" manufacturing process. "For Cybercab and Optimus, almost everything is new.""Eventually," he added, it will "end up being insanely fast."