A risk metric is a measure of how risky something is. For example, if you are thinking of investing in a company, you want to know how risky it is. The risk metric would show you how likely it is that the investment will make or lose money. It can also help you decide what steps you need to take to reduce the risk of the investment being a bad one. So, in a nutshell, a risk metric is a way of helping you measure and understand the risk of doing something.