Liquidation Engine

In decentralized lending and derivatives platforms, there are no credit scores. To borrow money or trade with leverage, you must provide "collateral" (like ETH). If you borrow $100 worth of stablecoins against $150 worth of ETH, you are "over-collateralized." But if the price of ETH drops to $110, the protocol is at risk: if the price drops much further, your ETH won't be worth enough to pay back the $100 loan. The "liquidation engine" is the automated system that steps in to sell your ETH before that happens.

Liquidation engines work by monitoring the "health factor" of every account. When the health factor drops below a certain threshold (the "liquidation point"), the engine opens up the account to "liquidators." These are usually third-party bots that pay off the user's debt in exchange for taking the user's collateral at a discount (a "liquidation penalty"). For example, a bot might pay the $100 debt and receive $105 worth of the user's ETH. This 5% discount is the profit incentive that ensures bots are always waiting to keep the protocol safe.

For investors, understanding the liquidation engine of a protocol is vital before using leverage. A "slow" or "inefficient" liquidation engine can lead to "bad debt." If the market crashes so fast that the engine can't sell the collateral in time, the protocol loses money, which can affect depositors. For traders, the risk is "getting liquidated" during a "wick"-a sudden, temporary price drop that triggers the engine even if the price quickly recovers. High-quality protocols use "price oracles" that smooth out these spikes to protect traders from unnecessary liquidations.