The accident that did not happen

On a residential street in Madinah, a few years ago, the municipality added speed bumps outside a primary school and painted the kerb. Drivers complained for a month. Then they stopped noticing.

Nobody on that street talks about the speed bumps now. There is nothing to talk about. Children cross in the morning, cars slow down without thinking, and the afternoons pass without incident. The street simply behaves the way people assume a street outside a school should behave.

That is the first difficulty with any measure taken for the common good. When it works, the result is an absence. No accident, no ambulance, no story. And because we expected the world to carry on normally anyway, we give the measure no credit for keeping it that way. Good outcomes that persist are almost invisible.

The second difficulty is the mirror image. Suppose one evening a car does clip a cyclist on that street, despite the bumps. Within a day someone will say the bumps were pointless. What nobody can see is the version of the street without them, where cars come through at twice the speed and the same evening ends much worse. A measure that falls short of perfect gets judged against perfection, not against doing nothing.

Put those two together and you get a steady pull in one direction. The things that quietly worked start to look unnecessary, and the things that partly worked start to look like failures. Given a few years, it becomes easy to argue that none of it was needed.

Some measures really are useless, and they deserve to be questioned. But it is worth asking, before deciding, what the street would have looked like without them.

The ones that work are the hardest to see, because what they produce is nothing at all.