"The apex of the pyramid measures how many things the code does, and how reliable it is." This is at the end of the article as the 5th "vertex". Nothing more

"The apex of the pyramid measures how many things the code does, and how reliable it is." This is at the end of the article as the 5th "vertex". Nothing more on this. The approach is interesting but without clear understanding of how you measure this 5th vertex or how you contain the other 4 while scaling into the 5th, you have a half-baked pyramid.