What can I say back to reply to my peer to add to your conversation The opportunity cost of capital ties into the DCF analysis. If you have money to invest you can essentially either make that money work for you and make it grow by investing it or you could loose money depending on how it was invested. An example I could give is I pay extra into my 401k its then distributed through stocks. I don't necessarily know which stocks it is being distributed through however it helps my money grow as long as I don't touch it otherwise, I have to pay a penalty fee. Another example I could give is when I bought my house, I used my savings to buy a house I got the house pretty cheap. It requires some work. However, since I have bought my house the value of my house is worth more than what I have in it now