If the goal is to make people drive slowly in general, FUD might be more effective. If the goal is to make people slow down in places where they really do need

If the goal is to make people drive slowly in general, FUD might be more effective. If the goal is to make people slow down in places where they really do need to slow down (e.g. before curves), visible warnings might be more effective. Outside of large cities, most of Korea has a mountainous terrain. A highway with an official speed limit of 110km/h can be perfectly safe to drive at 130km/h in one stretch but dangerous to drive at 90km/h in another stretch just a few km away. So I think it makes sense for the Korean police to focus on making people drive more slowly in some places than in others. Maybe the priorities should be different in a large flat country like Australia.