The source of the disconnect between San Francisco's transit-first heart and its car-centric hand is an arcane engineering measure called "level of service," or LOS. In brief, LOS suggests that whenever the city wants to change some element of a street — say by adding a bike lane or even just painting a crosswalk — it should calculate the effect that change will have on car traffic. — Eric Jaffe
Changing a city from being car-centric isn't just a matter of building better bike lanes and drawing up better bus routes. Sometimes, developers have to go up against restrictions which won't let them build at all if it interrupts too much car traffic.