“Supply and demand of products.”
Von Mises classic is called “Human Action”.
Capitalism is how humans act when they don’t have a gun to their head or a boot on their neck.
Costs for products, either rising and lowering costs, due to the supply and the normal demand of product.
For example, right now we’re having a manufactured shortage in the supply of eggs - (by burning millions of chickens, closing farms, etc.) and the cost has increased because the demand has stayed the same, but the supply has dropped. So, until the demand drops or the supply increases, the costs will remain high.