Even with those huge round mirrors that are attached to the bottom of the regular mirror mounts, they can't see & watch everything.
Sometimes they have to get out of the seat, or even the cab to see the what, who, & where is the next step to get lined up with the tanks & the tank covers.
I have to open my door, to position my Ram exactly in its parking spot.
So i have about a 6 inch square that my front tire must be in
so i have a cement line that my drivers door lines up with, when i am parked correctly
I can't see those cement lines, without opening my door, i am too short to lean my head out through the window