Earlier quoted context omitted.
How can this make sense? If the collateral is X, then the borrowed amount (Y) has to be less then X. Why lend anything in the first place, when that means you can only spend Y while otherwise you could have spent X which is more?
This happens quite regularly in the world of margin trading. Imagine the following: 1. I own ETH, and want to hold my ETH position so I can enjoy price increases, but I need liquidity to live my day to day life and, well, it's hard to pay for things with ETH. 2. Instead of selling ETH and exiting my position, I put ETH up for collateral and borrow a stable-coin (like DAI) against it. That way, I maintain my price exp…
A lends 10 Xcoins to B. B puts 11 Ycoins into escrow. A will either get back 11 Xcoins or 11 Ycoins.
If Xcoins rise in price relative to Ycoins, B is happy and A is sad.
If Xcoins fall in price relative to Ycoins, B is sad and A is happy.