You can earn above average rates of return because peer-to-peer lending eliminates the bank function. That means that you participate in nearly the entire interest rate being paid by the borrower, rather than the less than 1% that you will typically earn on certificates of deposit. And you can reduce your risk by investing in slices of hundreds of different loans.
How much will you make? I think my best month with Google AdSense was almost $5,000 over the last ten years. That amazing month blew my mind since it was actually near the beginning of my blogging journey. When you go from making zero to $5,000 in a month, that will rock your world. For me, it also got me even more excited because I knew there were other ways to monetize.