Most startup post-mortems cite "running out of money" as the cause of death. That is a lazy diagnosis. Running out of cash is merely the final symptom. The actual disease is almost always an operator who mistook an accounting projection for spendable cash, looked only at net burn, and woke up to find their runway had been cut in half overnight. When revenue looks steady, tracking cash feels straightforward. You look at your monthly burn, divide your bank balance by that number, and tell your board you have eighteen months of...