You are managing a small team. You are meant to make sure they work hard. Monitoring is costly and you would like to shirk your responsibilities. But your monitoring is observable to the worker bees. They incur no costs to observe your effort. If you shirk your duties, there will be payback from the workers. There is always the possibility that they turn you in to your supervisor.  This could be a deliberate act. More likely, it is inadvertent because “loose lips” that sink ships. So, you are left with no choice but to monitor. And since you are monitoring, the workers are left with no option but to work. Everyone is worse off. If only the workers could keep their mouths shut and the manager could shirk.