Technology can have unintended consequences. Self-driving cars are supposed to reduce traffic accidents and fatalities, increase mobility, and generally usher in a new era of safety — but they may also turn people into jackasses.

Last night, Greylock partner Josh Elman had an encounter with one of Waymo’s self-driving cars outside his California home. He saw the minivan approaching as he was taking his trash to the curb. But rather than stand passively to the side as the vehicle passed like you would do with literally any other car, Elman says he ran toward it.

This is a really interesting idea that Elman is proposing, but let’s back up for a second. The idea that you should run at a self-driving car because you believe it will always stop for you is absurd. Please don’t play chicken with the self-driving cars. These are 4,000-pound steel machines. You are a sack of meat and sticks. It’s not a fair match.

In Elman’s defense, it’s not clear whether he ran at the Waymo minivan on purpose to see if it would stop for him, or if he just happened to run at a moving vehicle while he was taking out his trash. It may have been just a coincidence, in which case his reaction is definitely thought-provoking. I’m also intrigued by the idea that autonomous technology could herald a shift in the power dynamic between cars and people. But I would also like that dynamic to stay in place for a while longer while we hammer out the kinks in the system.

Elman’s tweet did make me think about what a shit show it’s going to be for the next few years, as self-driving cars become more ubiquitous on public roads and people get more bold around them. If I know anything about human beings, it’s that they love testing both the limits of technology and their own mortality. Some idiot is going to throw themself in the path of an oncoming autonomous vehicle because they believe the sensors and safety systems embedded within will prevent them from getting run over. It sounds ludicrous, but believe me: it will happen.

Remember when Tesla first introduced Autopilot in 2015? People couldn’t wait to upload videos sitting in the backseat while their cars drove “autonomously” down the highway. Tesla responded by updating its software to require drivers to keep their hands on the steering wheel for Autopilot. Which seemed like a smart fix until one driver figured out all you needed to do to fool the system was wedge an orange against the wheel to simulate the pressure of a human hand. People. Love. Tricking. Technology.

Look, autonomous cars aren’t perfect. They get into fender benders, have trouble navigating inclement weather, run red lights, and sometimes they can’t figure out what to do about taco trucks. The technology is improving, no question, but there’s a reason the majority of companies have human safety drivers behind the wheel. It’s a question of liability, but it’s also a fail-safe. People are unpredictable, and there’s very little room for error if this technology is going to catch on and change the way we get around.