I think perception is the largest part. The word “bus” conjures up a dirty, homeless-guy horror show to a lot of people, compared to the quiet elegance of a tra

I think perception is the largest part. The word “bus” conjures up a dirty, homeless-guy horror show to a lot of people, compared to the quiet elegance of a train conductor peacefully snipping your ticket in a leather chair. Second, in many cities, trains actually predate the highways. Third, trains have super high capacity, as do subways and light rail. You need more buses to keep up. However, buses are cheap, and there are things like extra-long articulating buses and double-deckers that can be used on high-volume or long-haul routes. I think buses actually have a practical edge here: instead of trains coming every hour, you could have a big bus come every 10 minutes, which smoothes out load at end stations. And if one breaks down, the other buses can just drive around it. If a subway breaks down in New York, it can cause delays that ripple out to the whole system.