Cruise’s driverless rides aren’t human-free, not yet. Today, two autonomous vehicle trainers sit in the front—one safety driver, with her feet resting on the brake pedal and her hands loosely around the wheel, and a helper in the passenger seat, who sits with laptop in lap, softly intoning directions and words of caution, sending messages to coworkers through Slack, and taking notes on the ride. (This is contrast with Waymo, Google’s self-driving car unit, which has taken drivers out of its test vehicles in a Phoenix suburb and plans to launch a completely driverless taxi service in a Phoenix suburb in a few months.)

So the whole thing felt very safe. I felt good about the well-being of the pedestrians and cyclists around me, too. The car gave a bike rider cycling next to the curb plenty of space—we inched behind him for minutes, refusing to deviate from our lane. And Chinchilla was terribly considerate to those approaching crosswalks, braking, hard, the moment it looked like a person might cross the street. Towards the end of the ride, the car began to make a left turn into a crosswalk, and a woman pushing a stroller on the sidewalk accelerated toward the street. Not the baby, I pleaded silently, before she turned to cross the perpendicular street instead. Our car, meanwhile, had jerked to a stop—in the middle of the intersection. Cruise employees later told me they’ve programmed their cars to anticipate the actions of pedestrians. But right now, they don’t always get it right.

For humans driving regular cars, these auto-matons must be a nuisance. They are slow—we stayed at about 15 to 20 miles per hour for most of our trip. They stop at the hint of danger, sometimes slamming on the brakes and throwing passengers forward in their seats. (I would not choose to ride in this self-driving car if I were, say, already suffering from a migraine.) And occasionally, they get confused and just kinda freeze. At one point, Chinchilla approached a public bus pulled over to the side of a one-way street. There was plenty of room to navigate around it. Chinchilla braked and considered its impending circumnavigation. And considered. And considered. About two minutes later, the safety driver finally flipped off the self-driving mode and piloted the car around the bus. No vehicles were waiting behind us, but, oh, if there had been—the honking! (Kyle Vogt, Cruise’s CEO, later told me the lidar sensors that usually determine how much clearance the vehicles have on their sides have been suffering from technical issues for the past few weeks, so the cars are even more cautious about going around obstacles then they normally are.)

Yes, these cars are more conservative than your uncle who forwards you those chain emails. Cruise says they’re programmed like that on purpose. “We will not launch until we have safety perfect,” General Motors President Dan Ammann said during Tuesday’s press event, referring to plans to put driverless cars on the road. (Vogt declined to answer questions about how it will determine what is safe enough.)

As a result, the cars are more likely to get hit than to be the hitters. According to mandatory reports filed with the California Department of Motor Vehicles, Cruise cars have been involved in 21 incidents in 2017 alone. Overall, that’s pretty good: Cruise won’t say how many miles of testing it has under its drive belt, but 100 vehicles operate in San Francisco, and the company tests 24 hours a day. Still, 13 of those fender-benders happened because the self-driving cars got rear-ended. If a human driver is tailgating, or texting, or letting her mind wander while behind a safety-conscious autonomous car, she could miss a quick and cautious brake. Cruise officials told me drivers should act normally around these testing robots—just drive like you always should, they said. Pay attention. But humans are flawed. And impatient. When they’re around these cars, people might have to drive better than they usually do. Maybe that’s asking too much.

Or, more likely, maybe these cars represent something all drivers, humans or not, should aspire to—it may not be long until riding in these cars feels more like riding with an experienced adult instead of a responsible teen with a learner's permit. And the teen is doing OK. During my ride, the car navigated around a garbage truck, a roundabout, and a dicey, crowded left-hand turn with the finesse and patience of a well-rested cab driver.

“Autonomous driving is the most challenging engineering problem of the decade, if not the century,” Vogt told reporters. If my quick trip through a quiet section of San Francisco is any demonstration—well, yeah. And GM is about to make these exercises a lot harder for itself. Last month, it announced it will start testing in downtown Manhattan. And a chorus of “I’m walking here!”'s rang through the streets.

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