Public transit sucks in the US for a simple reason. Autosprawl profitieers WANT it to suck.

Public Transportation Woes Are Not Just In Boston | Infrastructure & Construction Law: "Crisis in public transportation is a result of neglect over time and boils over, resulting in what we currently see in many major cities.  Things like chronic lack of investment, poor management, and a culture not conducive to implementing preventative measures, are just some of the contributing factors."