The red traffic light is important because it tells drivers when to stop. The green traffic traffic light is important because it tells drivers to go. But the amber traffic light is far the most important traffic light. The amber light warns drivers that they are going to have to stop soon, or go soon, but even more importantly than what the amber light tells drivers is that it allows for flexibility, it allows for human nature, for people who are going to go when they should be stopping and not go when they should be.
All systems should be built with human nature rather than against it.