Before anyone can consume a kilowatt-hour, a liter of water, or a bus ride, somebody has to get a copper wire, a pipe, and a road to their house. These fixed costs need to be recouped through long periods of use.
但接入这些网络需要付出固定成本。在你消费一度电、一升水或搭乘一次公交车前，必须先铺好铜缆、管道和通向你家的道路。这些固定成本需要通过漫长的使用期回收。