[willcosgrove]

It's artificial if the entity loaning you the money and setting the rate has no associated risk.

If I loan you money there's risk you won't be able to pay me back. So I decide what interest you would need to pay me for it to be worth it for me to take that risk. Lots of other people do that, and you get a "natural" rate of interest as you call it. Everyone offering you the loan has skin in the game.

But if the entity that prints the money says they'll loan you money, it doesn't matter to them if you can't pay it back. They set the money supply. If you don't pay back, they can take the value from everyone dealing in their money by printing more. This lack of risk allows them to undercut the rates of entities who would be taking on risk. Now you have an "artificially" low interest rate.