Deer paths became indian trails became dirt roads became the first paved highways in the southern US in a mere three to four centuries time.
Only with the advent of multilane roads and interstates have the old, natural routes been passed over. So, it’s easily observed. The best route is the best route and recognized by animals, Celts or even Romans. Who’d have thunk, lol?
Back at the height of adding school buildings in CA, I knew an administrator who recommended that the builders leave the sidewalks out in a new collge complex for the first year. He claimed that the students would wear paths into the ground and those were the places to lay the walks. I’m sure he was right, and it saved the lawns from getting ruined.