If you’re looking for wordless ways to criticize someone’s driving skills en route, nothing works better than grabbing the handle above your door and hanging on for dear life. Fondly known by many as “‘Oh sh**!’ handles,” these common car fixtures convey “You’re reckless!” about as well as shouting “You’re reckless!”

With other features like armrests and automatic-lock shoulder seat belts to help passengers steady themselves during bumpy rides, it might seem like grab handles should be a thing of the past. And yet, many modern cars still have them above every door, with the possible exception of the driver’s side. So what are they actually for?

According to Technology.org, grab handles are mainly there so people can climb in and out of cars with ease. If you’re getting into a large vehicle, for example, you might use the handle to hoist yourself up into the car, and then again to lower yourself back down onto the step or sidewalk without having to jump. For a small vehicle, the situation is pretty much reversed. The handles are especially useful for people with disabilities, older people, and pregnant people.

While designing the Mercury Monterey minivan in the early 2000s, a Ford Motor Company engineer named Jared Glaspell actually donned a pregnancy simulator to see what might make the vehicle more comfortable for expectant parents. “There were ‘aha’ moments,” Glaspell told The Detroit News in May 2003. “I became more aware of where the instrument panel controls were placed. I wanted more grab handles to get in and out of the vehicle.”

As for why the driver’s door often lacks a grab handle, there are a few possible reasons. For one, Nodum.org points out, the steering wheel can function as a makeshift grab handle, and it would also block your path if you were to raise or lower yourself into (or out of) the car via a grab handle above the window. Plus, drivers inclined to grab the handle while driving would be steering with just one hand, which could be a safety concern.

In short, grab handles are meant to make entering and exiting the car a more comfortable process. But if your passengers never seem to let go of them, maybe you do need to reassess your driving skills.

[h/t Technology.org]