At midnight, your newly launched aggregator protocol suddenly experienced an abnormal liquidation. In the blink of an eye, user assets disappeared, and the community exploded in outrage, yet the audit report claimed that your contract code was "flawless." How is that possible?

Often, the problem isn't in your code at all—it's in the data source you integrated.

This is not alarmist talk. DeFi developers are not just creators; they are also the first line of defense for user assets. When you decide to integrate a certain oracle service into your application, you're not just bringing in price data—you’re also taking on a long-term "risk-sharing" responsibility.

**Integration does not mean abdication**

Many developers naively believe: using a reputable oracle service means the data responsibility is transferred away. Wrong. Your responsibility begins the moment data enters the contract.

Do you truly understand how this data source updates? How are outliers handled? Are there delay tolerances and anomaly checks set in the contract? When network congestion causes data lag, will your liquidation mechanism trigger a chain reaction?

**Lessons learned the hard way**

One lending protocol suffered from this. They didn't set price delay tolerances. As a result, during a brief delay in the oracle network, arbitrage bots seized the opportunity to initiate large-scale low-collateral liquidations using outdated prices. Millions of dollars evaporated in an instant, and user trust was completely shattered.

Oracle services are useful tools, but how you use them and to what extent ultimately depends on your own judgment.