Standards are made based on experiences in production activities in the past who made a step-by-step improvement. But not all standards can be applied in areas of production. due to field conditions are always different, and different treatment of the product must also be different.
Imperfect in applicable standards common in the production process of a product. It may be caused by imperfections in terms of work procedures, employees who have the imbalance skill standards in the relevant processes, as well as production machines that are not applicable to existing standards.