This guy doesn't like people driving over his driveway, so he set down a large painted rock to tear apart the underside of cars that go past.
It's not clear why he placed the rock there. As one YouTuber said, "exactly what are you protecting the foot wide swath of gravel?"
Another commentor said, "They keep hitting the rock because people can't see it. He knows that, that's why he's got an account specifically for showing people hit the rock he's placed there knowing people will hit it. The bigger question is exactly what is the damage these people are doing by using the space in his driveway to turn around. How is it so offensive that he has to go out of his way to place a rock there he knows is going to damage their cars? Why is he so petty?"