DeFi is often sold to beginners with the catchy phrase, "Deposit crypto into the protocol and earn passive income." It may indeed look simple on the screen: connect a wallet, deposit tokens, and see an APY of 12% , 25% , or even 100%+ per annum. But behind this figure, there's almost always a complex economics: fees, loans, trading activity, token incentives, smart contract risks, and the behavior of other market participants.
The main question to ask isn't "how much are they paying?" but "what exactly are they paying from?" In DeFi, returns don't just appear out of thin air. If a protocol is paying interest to someone, it means there's a source of income somewhere—or at least a temporary subsidy.
**1. WHAT IS DEFI YIELD IN SIMPLE TERMS?
**DeFi stands for decentralized finance: blockchain-based services that operate through smart contracts. A smart contract is a blockchain program that automatically executes rules: accept a deposit, issue a loan, charge a fee, and conduct an exchange.
In DeFi , yield is the reward a user receives for providing capital to the protocol or taking on a certain amount of risk.
For example, a user can:
• give tokens to the credit protocol;
• add a couple of tokens to the liquidity pool;
• stake coins;
• block management tokens;
• participate in farming, that is, receive rewards for providing liquidity.
But it's important to note: DeFi yields are not like bank deposits. There's no guaranteed return, no traditional deposit insurance, and a coding error or sudden market movements could lead to losses.
**2. WHERE DOES INTEREST COME FROM IN DEFI?
**DeFi protocols have several main sources of income.
Interest from borrowers
In lending protocols like Aave or Compound, some users deposit assets, while others borrow them against collateral. Borrowers pay interest, and a portion of this interest is collected by liquidity providers.
A simple example: someone wants to borrow USDC, leaving ETH as collateral. They pay a loan interest rate. This money is distributed among those who contributed USDC to the protocol.
Here, the yield depends on the demand for loans. If there are many people willing to borrow, the rate rises. If there are few borrowers, the rate falls.
Trading commissions
On decentralized exchanges, users exchange tokens through liquidity pools. A liquidity pool is a shared reserve of two or more assets, such as ETH/USDC.
Liquidity providers receive a portion of the commission from each trade. The higher the trading volume, the more commission the pool can collect.
But here another risk arises: impermanent loss . This is a situation where, due to the price fluctuations of one token relative to another, the user receives less than if they simply held these assets in their wallet.
Token rewards
Many protocols incentivize users with their own tokens. For example, a user contributes liquidity and receives not only fees but also an additional project token.
This could significantly increase the apparent yield. But the question is whether this token has real value and sustainable demand. If rewards are simply printed and immediately sold by users, the token's price could fall and the yield could quickly disappear.
Staking income
In Proof-of-Stake networks, users can earn rewards for contributing to the network's security. Proof-of-Stake is a mechanism where validators confirm transactions by locking up their coins.
In DeFi, this yield is often utilized through liquid staking. Users stake an asset, receive a liquid token, and can then use it in other protocols.
**3. APY and APR: WHY NUMBERS IN THE INTERFACE CAN BE DECEIVING
**In DeFi, two commonly used metrics are APR and APY .
APR is the annual interest rate without compounding.
APY is the annualized yield after reinvestment, meaning when the received rewards begin generating income again.
To put it simply, APY usually appears higher because it assumes that profit is continually added to the principal.
Formally, the difference is related to the effect of compound interest: where r r is the annual rate and n n is the number of accrual periods.
But in the reality of DeFi, this formula doesn't guarantee a final outcome. Rates fluctuate, token prices fluctuate, network fees fluctuate, liquidity wanes, and protocols are updated. WEEX, in its explanation of APY in crypto, specifically emphasizes: a high APY may seem like passive income, but it's important for investors to understand the risks and the mechanics of accrual.
In other words, the APY displayed on the screen isn't a promise. It's a calculation based on current conditions.
**4. REAL YIELD: TRUE PROFITABILITY OR MARKETING?
**Following the DeFi boom, the market has begun to talk more about " real yield." This typically refers to returns that come not from the printing of new tokens, but from the actual activity of the protocol: fees, interest, and trading volume.
For example, if a decentralized exchange generates fees from exchanges and shares them with participants, this is closer to a real yield. If, however, profitability is based solely on the distribution of new tokens, the model may be less sustainable.
1CryptoBlog's analysis of DeFi returns in 2026 notes that return analysis cannot be reduced to the simple formula "if there's TVL and fees, there's income." It's important to consider unit economics, incentives, margins, risks, and user behavior.
TVL stands for Total Value Locked, or the total value of assets locked in the protocol. A high TVL may indicate popularity, but it alone does not prove sustainable profitability. A protocol can attract a lot of capital through temporary rewards, only to lose it when the incentives expire.
**5. WHY HIGH RETURN OFTEN MEANS HIGH RISK
**If a protocol offers returns significantly higher than the market, there's usually a reason. Sometimes it's the project's early stages and an attempt to attract users. Sometimes it's compensation for risk. Sometimes it's an opaque or weak economics.
There are several questions worth considering:
• Do they pay from real commissions or from the issuance of new tokens?
• Who is the other party to the yield?
• Why are borrowers willing to pay such a rate?
• Is it possible to quickly exit a position?
• Is there a risk of stablecoin losing its peg?
• Was the protocol audited?
• Is there a dependency on bridges, oracles, and third-party services?
An oracle is a service that feeds external data, such as an asset's price, to smart contracts. If the oracle is inaccurate or attacked, the protocol may malfunction.
The author of the Zen article aptly identifies one of DeFi's main problems: people often look only at the interest rate without understanding how the protocol actually pays it. This is perhaps the most basic filter for any DeFi strategy.
**6. WHY DEFI YIELD CHANGES
**Returns in DeFi are almost never stable. They depend on the supply and demand of capital.
In lending protocols, the rate rises when many users want to borrow an asset, and falls when there is too much liquidity and few borrowers.
In liquidity pools, profitability depends on trading volume. If volumes fall, fees decrease. If too many liquidity providers join the pool, fees are distributed among a larger number of participants, and each participant's profitability may decrease.
The market is already showing that the era of "easy money" in DeFi has become less evident. CoinDesk wrote in April 2026 that DeFi yields have significantly declined and, in some places, no longer appear attractive compared to traditional savings products, especially given the risks of smart contracts and regulation.
This is a significant shift. The market is maturing: high returns are no longer perceived as the norm, but rather require explanation.
**7. KEY RISKS TO DEFI INCOME
**DeFi returns always come with risk. The main risks are:
• Smart contract risk – an error in the code can lead to loss of funds;
• market risk – the token price may fall sharply;
• Liquidity risk – exiting a position may be difficult or expensive;
• oracle risk – incorrect price data can cause disruptions;
• Bridge risk – bridges between blockchains are often the target of attacks;
• governance risk – admin keys or team decisions can impact the protocol;
• Regulatory risk – the rules for DeFi continue to change;
• The risk of complex strategies - multiple protocols in one chain increase vulnerability.
A Teletype article on DeFi returns cites examples of major incidents in 2026, including hacks and collateral issues, demonstrating that even large protocols and popular strategies are not immune to systemic failures .
The main conclusion is that profitability should be assessed together with risk, not separately from it.
**8. HOW TO READ DEFI RETURNS WITHOUT ILLUSIONS
**Before you get excited about a high rate, it's helpful to break it down.
Conventionally, profitability can consist of:
• base interest rates from borrowers;
• trade commissions;
• token rewards;
• staking rewards;
• bonuses from affiliate programs;
• temporary incentives to attract TVL.
The most stable part is the one that comes from real demand: trades, loans, and product usage. The most fragile part is the one that depends on the constant issuance of the token.
If a protocol pays 30% 30% annually, but 25% 25% of that is rewarded in a token that falls in price, the actual result may differ greatly from the pretty figure in the interface.
RESULT
Income in DeFi isn't magical. It comes from specific sources: loan interest, trading fees, staking, token rewards, and user activity. The clearer the source of income, the easier it is to assess the sustainability of the model.
A high APY by itself proves nothing. It could be the result of genuine demand, or it could be a temporary subsidy or compensation for significant risk.
DeFi gives users more freedom, but it also shifts more responsibility. So the key question is simple: who pays the interest, why do they do it, and what risk do I take on for that interest?
Top comments (0)