It may have to do with for example, the VTA expanding service (in miles of track) but the ridership not going up to match. Also, rail in places like the bay area, or even buses, just can't justify the opex given the relatively light ridership. Mass transit is rarely profitable (financially self sustaining) but many transit systems, given housing density and commercial/residential patterns, in the US, are woefully in deficits.<p>Edit: To add, I mean this in terms of more than just the high density corridors and terminus to terminus lines. I mean if you live in Almaden Valley and want to get to East San Jose or you want to get to Milpitas. Or if you want to get from The Marina in SF to the Outer Sunset. Most SF transit is designed to pull people in and out of the old downtown core (even MUNI uses the terms "inbound" and outbound" which tell you a lot about the passenger flow they had in mind. There is no "ring" line or N-S LRVs in SF.