What is a ‘Liquidity Pool’?

To illustrate why more money helps, let’s break down how Uniswap works. 

Let’s say there was a market for USDC and DAI. These are two tokens (both stablecoins but with different mechanisms for retaining their value) that are meant to be worth $1 each all the time, and that generally tends to be true for both.

The price Uniswap shows for each token in any pooled market pair is based on the balance of each in the pool. So, simplifying this a lot for illustration’s sake, if someone were to set up a USDC/DAI pool, they should deposit equal amounts of both. In a pool with only 2 USDC and 2 DAI it would offer a price of 1 USDC for 1 DAI. But then imagine that someone put in 1 DAI and took out 1 USDC. Then the pool would have 1 USDC and 3 DAI. The pool would be very out of whack. A savvy investor could make an easy $0.50 profit by putting in 1 USDC and receiving 1.5 DAI. That’s a 50% arbitrage profit, and that’s the problem with limited liquidity.

Incidentally, this is why Uniswap’s prices tend to be accurate, because traders watch it for small discrepancies from the wider market and trade them away for arbitrage profits very quickly.

However, if there were 500,000 USDC and 500,000 DAI in the pool, a trade of 1 DAI for 1 USDC would have a negligible impact on the relative price. That’s why liquidity is helpful.

Similar effects hold across DeFi, so markets want more liquidity. Uniswap solves this by charging a tiny fee on every trade. It does this by shaving off a little bit from each trade and leaving that in the pool (so one DAI would actually trade for 0.997 USDC, after the fee, growing the overall pool by 0.003 USDC). This benefits liquidity providers because when someone puts liquidity in the pool they own a share of the pool. If there has been lots of trading in that pool, it has earned a lot of fees, and the value of each share will grow. And this brings us back to tokens.

Liquidity added to Uniswap is represented by a token, not an account. So there’s no ledger saying, “Bob owns 0.000000678% of the DAI/USDC pool.” Bob just has a token in his wallet. And Bob doesn’t have to keep that token. He could sell it. Or use it in another product. This helps to explain why people like to talk about DeFi products as “money Legos.

So how much money do people make by putting money into these products?

It can be a lot more lucrative than putting money in a traditional bank, and that’s before startups started handing out governance tokens.

Compound is the current darling of this space, so let’s use it as an illustration. As of this writing, a person can put USDC into Compound and earn 2.72% on it. They can put tether (USDT) into it and earn 2.11%. Most U.S. bank accounts earn less than 0.1% these days, which is close enough to nothing. 

However, there are some caveats. First, there’s a reason the interest rates are so much juicier: DeFi is a far riskier place to park your money. There’s no Federal Deposit Insurance Corporation (FDIC) protecting these funds. If there were a run on Compound, users could find themselves unable to withdraw their funds when they wanted.

Plus, the interest is quite variable. You don’t know what you’ll earn over the course of a year. USDC’s rate is high right now. It was low last week. Usually, it hovers somewhere in the 1% range.

Similarly, a user might get tempted by assets with more lucrative yields like USDT, which typically has a much higher interest rate than USDC. Monday morning, the reverse was true, for unclear reasons; this is crypto, remember. The trade-off here is USDT’s transparency about the real-world dollars it’s supposed to hold in a real-world bank is not nearly up to par with USDC’s. A difference in interest rates is often the market’s way of telling you the one instrument is viewed as dicier than another.

Users making big bets on these products turn to companies Opyn and Nexus Mutual to insure their positions because there’s no government protections in this nascent space – more on the ample risks later on.

So users can stick their assets in Compound or Uniswap and earn a little yield. But that’s not very creative. Users who look for angles to maximize that yield: those are the yield farmers.

In the next article we will cover what is yield farming. Click here to go: https://blog.brozbot.com/2020/09/22/what-is-yield-farming/.