All the money invested in purchasing things the system intends to sell (including equipment and buildings).
One of the most radical ideas in The Goal is its critique of traditional efficiency metrics. Most managers try to keep every worker and machine busy 100% of the time to lower the "cost per piece." the goal by eliyahu m. goldratt pdf
"The real goal of any business is to make money by increasing throughput while simultaneously reducing inventory and operational expense." All the money invested in purchasing things the