$1)$ What is "spoilage?

$2)$ What is "normal" spoilage?

$3)$ What is "abnormal" spoilage?

$4)$ Why do you think it's important to distinguish between normal and abnormal spoilage?

$5)$ If you agree that expected losses from spoilage should be worked into the cost of our product and, accordingly, the price, how do you recommend we capture the expected losses $($the normal spoilage$)?$ How would we make sure that each chair got it's fair share of expected spoilage?