Don&#x27;t forget inflation risk.<p>Tomorrow a buck is worth about a buck.  Given some nice 70s era stagflation, in a decade a buck might only be worth fifty cents.  Loaning one dude a buck and getting fifty cents back isn&#x27;t all that different than loaning out ten dimes and getting only five paid back.<p>There is also downside risk.  Your financial life will be about the same tomorrow as it is today, so I can reasonably estimate the odds of getting a buck back if you need change for the vending machine or whatever.  Ten years from now, well, hard to say how many bad things can happen to someone in ten years.