““Putting a number in a day-to-day context is critical. For instance, years ago, Cisco Systems was contemplating whether to install a wireless network for its employees (a no-brainer today, but not at the time). The company had calculated that it would cost roughly $500 per year, per employee, to maintain the network. Was that worth it? Hard to say, since we don’t have much intuition about $500 yearly expenses.””