Asphalt, like glass, is an amorphous solid. When a heavy truck sits still on asphalt, asphalt will flow out from under the tires. Not only do you get a depression and eventually a pot hole where the tire was, and you get a little hill next to it.
You just about need an offroad vehicle to avoid hitting the street.
Doesn’t just happen on hills you can see this phenomenom on flat intersections too that have seen a lot of nearby construction vehicles (cement trucks, dump trucks, etc are probably the worst).
Moreover, when a heavy vehicle like a loaded passenger bus has to accelerate from stationary on a hill, it exerts incredible force on the asphalt below it.