Eberhard is not a big believer in autonomous driving—and he worries about Musk’s focus on it. In an interview published by Insider today, he suggested it could be dangerous.

On Wednesday, the National Highway Traffic Safety Administration announced that Tesla will recall more than 360,000 vehicles equipped with its Full Self-Driving (FSD) beta software because of apparent crash risks. (Musk takes issue with the word “recall” because the required fixes will be done via an over-the-air software update instead of in service centers.)

Eberhard noted of Tesla’s early days, “all this FSD autonomous, autopilot crap—none of that existed when I was there. We were still busy trying to make the car work and we never thought about that at all. That came later. That requires a much, much bigger budget than we had.”

Musk has prioritized it. Last summer, in an interview with the YouTube channel “Tesla Owners Silicon Valley,” he said that achieving self-driving technology is the “difference between Tesla being worth a lot of money or worth basically zero.” 

Musk said FSD mode was key to making Teslas compelling enough that the carmaker could challenge entrenched automakers.

Wary of Tesla’s full self-driving feature

Eberhard has different thoughts. “In my opinion, we need to get out of the habit of thinking about all of this autonomous stuff as being connected to EVs,” he told Insider. He said he appreciates “safety-oriented systems” like the driver-assist features that current Teslas come with.

It’s the autonomous driving that bothers him. The FSD feature requires drivers to monitor it, but it enables Teslas to automatically park, enter highways, change lanes, and stop at traffic lights.

“I think the technology is way too immature to be laying on the road,” Eberhard said. “I mean, this is my cautious nature, but I would have had a really hard time releasing software that is as buggy as that onto the roads.”

Eberhard isn’t alone. Last weekend, tech CEO Dan O’Dowd spent nearly $600,000 on a Super Bowl ad warning Americans about Tesla’s FSD feature. He tweeted, “I am trying to remove the worst, most incompetently designed, developed, and tested automotive product on the market.” 

Tesla threatened O’Dowd and his group the Dawn Project with legal action last August after they released a viral video that showed a Tesla purportedly in FSD mode hitting a child-sized mannequin. In a cease-and-desist letter to O’Dowd, Tesla called the Dawn Project’s tests “seriously deceptive and likely fraudulent.”

Tesla has faced lawsuits and regulatory scrutiny over its autonomous driving feature. And last month, reports emerged that a 2016 video demo about Tesla’s FSD mode had been, according to testimony from a company engineer, staged.

Fortune reached out to Tesla but did not receive an immediate response.

Eberhard said that, in his mind, thinking of a car as a software platform is a mistake.

“I have an iPhone, and every time I get a software update there’s bugs in there,” he told Insider. “These bugs mean, for example, that occasionally my news-feed app crashes. That’s not a big deal, because it’s just an annoyance on an iPhone. But that kind of a bug shows up in the software that controls, for example, my brakes or the steering, it can kill you.”