A yield that looks like 200% APY on paper might actually be negative after accounting for all the risks. Building a framework to assess DeFi yields requires disaggregating the return into its components and pricing the associated risks, even if that pricing is approximate.
The first step is identifying where the yield actually comes from. Sustainable yields have identifiable economic sources: borrowing demand (lending protocols), trading fees (DEX liquidity), or real-world revenue streams (RWA protocols). When you cannot identify the source, the yield is coming from somewhere you do not want it to, usually token inflation that dilutes existing holders.
Smart contract risk is the most obvious and often least priced risk. Every DeFi protocol interaction exposes you to the possibility of a bug or exploit draining funds. Audit reports help but do not eliminate risk. Some of the largest exploits hit audited protocols. A rough framework is to discount yields based on protocol age and audit status. A battle-tested protocol running for two-plus years with multiple audits carries less smart contract risk than a new fork launched last week.
Token price risk in yield-bearing positions is frequently underestimated. If you provide liquidity in an ETH/USDC pool earning 30% APY in the pool's governance token, you are exposed to ETH price risk, pool token price risk, and the governance token price risk. A 50% drop in ETH can easily wipe out a year of yield income.
Impermanent loss, which deserves its own analysis, is a specific form of this risk for liquidity providers. The divergence loss between the two assets in a pool can exceed the fees earned, especially during trending markets.
Liquidity risk often gets ignored during good times. Your LP position or lending deposit might show an impressive yield, but can you exit at the displayed price? During market stress, everyone tries to withdraw simultaneously. Protocol TVL can drop faster than you can unwind, especially for less liquid tokens or pools with lock-up periods.
Counterparty risk in DeFi is the risk that other protocol participants default or act adversarially. In lending protocols, this manifests as bad debt when collateral drops faster than liquidations can process. Aave and other protocols have accumulated bad debt from exactly this scenario.
Regulatory risk applies to yield strategies involving regulated activities. Protocols offering yield on tokenized securities, real-world assets, or stablecoin lending may face regulatory action that freezes or restructures the protocol. This is particularly relevant for US-based users interacting with protocols that may or may not be in compliance.
A practical risk scoring framework might look like this. Rate each risk on a 1-5 scale (1 being lowest risk): smart contract risk, token price risk, impermanent loss risk, liquidity risk, counterparty risk, and regulatory risk. Sum the scores. Subtract that risk score from the advertised APY to get a rough "risk-adjusted yield." A 50% APY with a high risk score might be equivalent to a 10% APY on a blue-chip protocol with a low risk score.
The most consistent DeFi returns come from simple strategies on established protocols: lending stablecoins on Aave, providing liquidity in major pairs on Uniswap, or staking on validated liquid staking protocols. The yields are lower but the risk-adjusted returns tend to be better than chasing the highest number on the latest protocol.