What is product costing?
Product costing works out what it costs to make one unit of a part. It adds purchased material and scrap from the bill of materials, setup, labour and machine time from the routing, subcontract and external operations, and overhead. A standard cost is the released figure the business plans and quotes against.
The cost sheet usually lives in one person's spreadsheet. It uses last year's prices, forgets the scrap on a seat ring and nobody can say where the machine rate came from. When engineering proposes a change, the cost impact on the ECR is a guess, and it can take weeks to get even that.