Case 1: Royal Mail Cost of Capital Why is it important to estimate a firm's cost of capital? What does it represent? Is the WACC set by market forces or by corporate managers? Explain why cost of capital had become a point of discussion for senior managers in the case. Case 1: Royal Mail Cost of Capital Why is it important to estimate a firm's cost of capital? What does it represent? Is the WACC set by market forces or by corporate managers? Explain why cost of capital had become a point of discussion for senior managers in the case