Reject is also known as waste or defective production and refers to the parts produced that did not meet quality standards at the first check. In the Six Big Losses, reject parts occur in either the steady-state production or during a start-up after a downtime event (reduced yield).
In addition to the information you provided, here are some additional details about rejects in production:
Reject parts can be obtained by subtracting the actual (good) production from total production.
Reject = Total Production - Actual (good) Production
Rejection rate(%) = (Waste Material Cost ÷ Total Cost of Production) × 100%
OR
Rejection rate(%) = (Total Units/Quantity of Waste Materials ÷ Total number of units/quantity produced) × 100%