>When there's snow on the road hiding lane markings, someone will come and clean it out.
In New England, snow can completely cover the road surface for days or even weeks at a time, and ever-changing piles of snow cover the curbs and parts of the lanes. Humans just choose a path without regard to where the lanes are in the summer. On some roads this turns a four lane road into a two lane road with a lane-width snow pile between the lanes. In a few spots it turns a two lane road into a one lane, with drivers from different directions taking turns.
Yeah, there were a few spots in my neighborhood that they gave up on trying to plow, but those of us with 4WD trucks were able to get through. Not sure how a self driving truck is going to know which snowbanks it can drive through/over and which it can't. Sometimes I couldn't tell until I tried. That was fun!
Now I really wish I had taken more photos that year specifically to illustrate this sort of thing.
In New England, snow can completely cover the road surface for days or even weeks at a time, and ever-changing piles of snow cover the curbs and parts of the lanes. Humans just choose a path without regard to where the lanes are in the summer. On some roads this turns a four lane road into a two lane road with a lane-width snow pile between the lanes. In a few spots it turns a two lane road into a one lane, with drivers from different directions taking turns.