Ridership v coverage. Who knew public transport planning was so complicated?
https://humantransit.org/2009/12/yet-another-transit-isnt-green-because-of-empty-buses-story.html
If public transit agencies were charged exclusively with maximizing their ridership, and all the green benefits that follow from that, they could move their empty buses to run in places where they’d be full. Every competent transit planner knows how to do this. Just abandon all service in low-density areas, typically outer suburbs, and shift all these resources to run even more frequent and attractive service where densities are high, such as inner cities. In lower-density areas, you’d run only narrowly tailored services for brief surges of demand, such as trips to schools at bell-times and commuter express runs from suburban Park-and-Rides to downtown. If you do such a massive shift of resources, I promise your productivity (ridership per unit of cost) will soar, and you won’t have as many empty buses.
The outcry would be tremendous, the politics toxic, the prospects for implementation zero. I would never propose it. But there’s no question that such a service change would dramatically increase ridership, dramatically reduce the number of empty buses, and thus improve how transit scores on the kind of tally that Cox and his allies propose.
Meanwhile, back in the real world, transit agencies have to balance contradictory demands to (a) maximize ridership and (b) provide a little bit of service everywhere regardless of ridership, both to meet demands for ‘equity’ and to serve the needs of transit-dependent persons.