The document discusses how cities have become more oriented towards cars over the past 80 years, costing $13 billion per year in lost productivity, but notes examples of movements like Park(ing) Day and pop-up cafes and plazas that have created temporary public spaces to make cities more pedestrian-friendly in an agile manner by gaining feedback and quickly implementing low-cost changes. It argues that cities should take an agile approach to development and policy by rapidly testing ideas rather than relying on long-term master planning.