This is really the problem for a lot of transit systems in the US. I guess you could say they operate below critical mass, so it's neither fast nor frequent enough, nor goes places people are or want to go in too many systems across the US. It doesn't help that our urban density levels suck.

Public transit also ends up being the last bastion for folks that society has discarded, and while I don't have a problem with helping people, a lot of folks will flat out refuse to ride public transit because they're terrified of getting harassed or having to exist in the same space as homeless people (I wish I was kidding). I think that some things that could be done with regard to that is to enforce some basic standards on public transit without shutting out the people who absolutely depend on it, such as: don't smell like you just came from a Magic The Gathering tournament, don't harass anyone else or cause a disturbance, and you have to be at least conscious enough to obey commands in order to ride.