Manufacturing turns components into finished products, and makes the books follow the physical truth of the factory floor. A work order says: make this many of this product, from this recipe. Materials leave the shelf at what they actually cost and gather in work in progress; finished goods come back at standard cost; and the difference between the two — the variance — is named and posted openly, never buried in a stock figure where nobody can see it.
The costing is deliberately materials-only, and the manual will not pretend otherwise: the work order captures what was consumed, not the labour or machine hours of the people who consumed it, because the application records none. What it promises is narrower and solid — every unit made carries the honest cost of what went into it, and every difference between plan and reality has a name and an account.