This is another one of those models no one pays attention to because it isn’t apparent. But once it is apparent it kicks ass. This model applies at scale, not as it scales. The idea is that when a system reaches a critical mass or limit, the behavior of the system can change dramatically. It can work better, or far worse. So the important thing is paying attention to small changes until you can judge when a critical threshold is reached. Judging where that critical threshold begins is stuff, and unless your a chemist, is probably best judged through experience. Stand on the shoulders of giants here. I have lots of these little rules of thumb in my work at a fintech company. These rules apply to our portfolios, customer lifecycles, and even relationships. Build up a list of breakpoints throughout your career. They’re powerful.
In the book Seeking Wisdom From Darwin to Munger, Peter Bevelin sums it up nicely.
Consider technological, physical, human, biological and mathematical constraints and limits. We can’t send signals faster than the speed of light. There are limits to how small or large something can be. Gordon Moore, one of the founders of Intel, predicted in 1965 that the number of transistors that could be economically produced and placed on a silicon chip would double every 18 months. In 1995 he updated he prediction to once every two years. Eventhually though, physical, engineering or economic limits may stops this from happening.