This paradigm looks to price as the cornerstone of supplier selection. It difficult to argue, at least on the surface, with using price to make decisions on suppliers.
However, having to compete and share business with others, paradoxically, adds uncertainty and reduces incentives to work hard at lowering cost. So one has to balance the need for lowest price against the need for lowest cost. The difference is that lowest price, as bid against others, may not result in the lowest cost.