There are two different measures of the value of something that sound a lot like each other: efficiency, which represents the value created in respect to the effort made, and efficacity or effectiveness, which on first glance seems to be only about the value created. You are efficient when you build a house with less material or finish a task in less time. You are effective when you manage to finish the task or build the house, when you get the job done. Yet no one will tell someone "Oh, you've built a highway in 30 years, that's efficacy!" (Hello, Romania!). Efficacy is when you consistently get the job done.
Imagine you are a chess player. You are efficient when you can beat people by moving faster than them, by thinking more in the same amount of time. This allows you to play faster and faster time controls and still win. However, think of the opposite situation. You start by being good at bullet chess and then the time controls get slower and slower. You are effective when you keep winning no matter how much time you have at your disposal. Efficacy is also when you keep winning games.
That was my epiphany. Take me, for example. I don't play better chess when I get more time to think. I am not fully using the resources available to me. I can give a lot of examples. I have money, more or less, so do I use it to the best of its value? Hell, no! I suck at both chess and finance. The point is that some people would do well with an average amount of resources, but then they would not do better with more of them. These are two faces of the same coin. One is the short distance lightning fast runner and the other is the marathon runner. Both of them are good at running, but in different resource environments.
Both efficacy and efficiency are relative values, value over resources, a measure of good use of resources: use few resources well, you are efficient, use a lot of resources well, you're effective. It's the difference between optimization and scalability.
Why does it matter? I don't know. It just seemed meaningful to explore this realization I've had, and of course to share it.
Take a good writer who wrote a masterpiece in between working and living. He achieved a lot with less. But what if you give him money so he doesn't have to work. Is he writing more books or better books? In our day and age, scalability has become more important than efficiency. If you provided value for 10 people, can you provide it to 100? It's more important than getting it to be 10 times better.
Can one apply scale economics to their own person? If I thought 10 times faster than everybody, would I have 10 times more thoughts or would I just learn to not think that fast, now that I have the time? You see, it seems that applied to a person, the two concepts are similar, but they are not. Thinking 10 times more thoughts in the same amount of time or taking 10 times less to think the same thoughts might seem the same, but it's the same thing if I compare listening to two people at the same time or listening deeply to a single person. Internally it seems the same, but the external effect is felt differently.
I don't have a sudden and transformational insight to offer, but my gut feeling is that trying to scale one's efforts - or at least seeing the difference to optimizing them - is important.