As the WACC is a simple average between the cost of equity and the cost of debt, oneâs instinctive response is to ask which of the two components is the cheaper, and then to have more of the cheap one and less of expensive one, to reduce the average of the two. Well, the answer is that cost of debt is cheaper than cost of equity. As debt is less risky than equity, the required return needed to compensate the debt investors is less than the required return needed to compensate the equity investors. Debt is less risky than equity, as the payment of interest is often a