Concerns the proportion of products arising from the production process that are found to be faulty or defective in some way. The number of rejects is usually expressed as a percentage of total products produced in a given period of time (ie number of rejects / total products produced in a trading period x 100 = X%). Rejects can be costly and can be caused by any one or a number of the following: failure to identify customer requirements, poor quality supplies, poorly maintained machinery, poorly motivated and committed staff.