Investors compare their required return to the expected return on an investment to assess the risk and potential return. The required return is the minimum rate of return needed to justify the risk of investing in a particular asset or portfolio. The expected return is the anticipated rate of return based on the investor's analysis. By comparing the two, investors can make informed investment decisions based on their risk tolerance and financial goals. This analysis helps investors determine whether an investment is worth the risk and whether the expected return is sufficient to meet their required return.