You are taking about the difference between fixed and variable cost.
Each company has their own method of dividing fixed and variable cost. For example, salaried employess may be a fixed cost in one company and a vaiiable cost in another.
Back to value added.
Examples of "value added" not related to product manufacture:
Janitors are fired as non essential. You go into the restroom everyday and there is no TP. Is the janitor value added or not?
An accountant doesnt work on a product line, doesnt sell products, doesnt ever touch the product, but processes the payment of the raw materials necessary to produce the product. Value added or not?
Payroll clerk makes sure you get payed. Value added or not?
Your factory is in a high crime area, petty theft, car break ins and muggings are common. You have security, a fenced, gated and secure compound. Value added or not?
Value added is a slippery slope.
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