Imagine an archipelago who’s inhabitants are waiting for shipments of goods. The ships have to navigate through these islands, sometimes at night. Initially their leaders taught each person on these islands that it was their religious duty to help light the way for these ships to pass through. So they all lit up their tiki torches on the coastline of their islands. Over the course of time however, people noticed that even though they forgot to light up their torches some nights, the other torches on the island were able guide the ships anyway, so some of them decided to

free ride

on their neighbor’s torches. Eventually it got to the point where there wasn’t enough light, accidents started happening, and one ship crashed, with the entire shipment lost. This is what is known as a

public goods problem