The real wordsTheory
Two kinds of input
The professors split the input box in two, and the exam expects both halves.
Consumable inputsUsed up in the process: raw material, and the cost of buying it.
Non-consumable inputsNot used up, and often not on the balance sheet: human capital (skills), intellectual capital (knowledge and innovation), social capital (networks and trust), and reputation, brand equity and customer loyalty.
Steel is consumed making a car. The welder's skill is not. Both went in.