Like earthquakes, revolutions are much better at destroying than building. There is an important asymmetry here, whose roots go all the way down to the laws of physics: It is possible to change things quickly for the worse. It only took two hours after the collision between a 767 and the South Tower of the World Trade Center to destroy it. But no one can build the World Trade Center in two hours. The only thing you can do with Rome in a day is burn it.
—Culture Making, p.58
A group of frustrated neighbors in the Dutch city of Delft finally got fed up about autos speeding down their street. One night, they dragged old couches and tables into the middle of the road, strategically arranging them so that motorists could still pass—but only if they drove slowly. The police eventually arrived and had to admit that this scheme, although clearly illegal, was a good idea. Soon the city was installing its own devices to slow traffic, and the idea of traffic calming was born—an innovative solution now used across the globe to make streets safer.