It'll be decades before autonomous cars are widespread on the roads -- and even then, they won't be able to drive themselves in certain conditions, the chief executive of Waymo said Tuesday.
John Krafcik, head of the self-driving car unit of Google parent company Alphabet, said that though driverless cars are "truly here," they aren't ubiquitous yet. And he doesn't think the industry will ever be able to drive at any time of year in any weather and any condition, the highest driving rating. Driving in all conditions can be difficult for humans too, he noted.
"Autonomy always will have some constraints," he said.
"It's really, really hard," Krafcik said. "You don't know what you don't know until you're actually in there and trying to do things."
Waymo started working on autonomous vehicles in 2009 and famously became embroiled in a highly publicized lawsuit with Uber earlier this year over stolen self-driving tech.
Video: AutoComplete: Waymo completes 8 million test miles on public roads
Self-driving cars are a hot topic in the auto and tech industries. Automakers, including Toyota, Ford and Volvo, all have projects underway. Besides Google and Uber, other Silicon Valley giants, including Apple, Intel and Tesla Motors, are betting on the tech.
Self-driving cars aren't making money yet, but that could change soon. Once thought of as far-off future tech, driverless vehicles could be cruising city streets within the next 10 years, transforming both the multitrillion-dollar auto industry and Uber's burgeoning ride-hailing business.
Krafcik said trucking is one area where self-driving vehicles could soon appear in the next couple of years. The US currently lacks about 50,000 truck drivers required for logistics, and that'll grow to a shortage of about 275,000 over the next couple of years, he said.
"The trucking shortage is now," Krafcik said. "Moving goods on freeways to hub to hub is fairly straightforward."
CNET's Dara Kerr contributed to this report.
First published Nov. 13, 9:25 a.m. PT.
Update, Nov. 15 at 3:45 p.m.: Adds additional background information.
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