My wife was just telling me a story about how the municipalities around us replaced the incandescent stoplight bulbs on the streets with LEDs, citing how much electricity use they would save. However, they didn’t realize the heat that incandescent bulbs put off melts snow in the winter, so the bulb is always visible. In their first year, the LEDs are covered up by snow storms and seeing the lights is hard, or impossible in some intersections. Now, each brand new light needs a heater added to it to melt snow.
When they calculated the return-on-investment for LED replacement, they calculated all the saved electricity. However, some of that saved electricity now needs to be diverted to heaters to melt excess snow. If they add intelligence to make them only turn on as needed, that will still produce savings, but again will cost more. Missing this in the original calculation makes the whole Return-on-Investment incorrect. The cost/benefit analysis may not even be in the right ballpark now to the point where if they hadn’t already done the project, they wouldn’t move forward with it under the new calculation.
This is common in the world. It’s far more common than we think. Most people value nearly everything incorrectly. That’s what a market is. How often do you think someone sells a car and one person walks away paying too much, while the other person received more money than they should have? Every time if you ask enough people. That’s what a market is.
If you want to be someone who makes good decisions, it’s imperative to learn to use as much creativity and empathy as possible to see all of the “intangibles” that others don’t. Forgetting heaters is easy when the previous stoplights didn’t need them. Thinking through all the assumptions being made is imperative, and it’s hard work. That’s what makes it valuable.
P.S. It also might be that when you are dealing with people, this is true as well. The last person maybe didn’t need praise. The last person maybe didn’t need training. The last person didn’t need any resources. The current person isn’t the last person, don’t treat them that way.