Automobiles are often conveniently tagged as the villains responsible for the ills of cities and the disappointments and futilities of city planning. But the destructive effects of automobiles are much less a cause than a symptom of our incompetence at city building. The simple needs of automobiles are more easily understood and satisfied than the complex needs of cities, and a growing number of planners and designers have come to believe that if they can only solve the problems of traffic, they will thereby have solved the major problems of cities. Cities have much more intricate economic and social concerns than automobile traffic. How can you know what to try with traffic until you know how the city itself works, and what else it needs to do with its streets? You can’t.
– Jane Jacobs, Death and Life of Great American Cities
Bicycle advocates can find many examples to support Jacob’s quote. It’s relatively easy to define transportation problems in terms of motor vehicle levels of service (LOS) and average daily traffic (ADT). LOS and ADTs are easily measured and quantified for motor vehicles.