I was sitting at a traffic light today, and cars were backed up for at least 50 metres on each side of the road waiting for the lights to turn green.
Up ahead and in the distance, I heard the sound of an ambulance approaching. I saw its lights reflecting off cars and buildings before it arrived at the backed-up line of cars.
The traffic lights in front of me turned green, but no car moved. All of us remained in place, allowing the ambulance to use both sides of the road to weave through and get past the gridlock with ease.
Systems are typically designed with order being the base case or day-to-day expectation. But when there is an emergency and the system is under stress, it only works when everyone knows the rules. And crucially, when everyone know how to implement the rules in unison.