Aave's Risk Shift: How a Lending Protocol Protected Lenders While Leaving Borrowers Exposed

A Bank of Canada staff paper has exposed a critical tradeoff in Aave V3's lending model: the protocol successfully avoided bad debt in 2024, but only by offloading liquidation losses directly onto borrowers.

The research, which analyzed transaction-level data from January 27, 2023, through May 6, 2025, reveals that Aave V3 maintained zero non-performing loans across Ethereum's lending market. Overcollateralization requirements and automated liquidation mechanisms proved effective at protecting lenders—positions were typically liquidated before collateral values fell below outstanding debt levels. But here's the catch: that safety net for creditors came at a steep price for those on the borrowing side.

The Mechanics: How Aave Dodged Bad Debt

Aave V3's architecture relies on automated risk controls rather than traditional credit underwriting. Borrowers must post significantly more collateral than they borrow, and the protocol automatically liquidates positions when they breach predetermined risk thresholds. This design eliminated unrecovered losses for lenders but simultaneously constrained capital efficiency compared with traditional lending systems—a fundamental tension in decentralized crypto trading.

The Bank of Canada's analysis shows this automation works. By liquidating before collateral values deteriorated too far, the protocol contained lender losses throughout the sample period. But the paper emphasizes a critical detail: this protection came through a direct transfer of risk to borrowers during liquidation events.

Recursive Leverage: The Hidden Demand Driver

One of the study's most revealing findings concerns what's actually driving Aave V3's lending volume. Recursive leverage—the practice of repeatedly borrowing against collateral, redeploying borrowed assets as new collateral, and borrowing again—accounted for over 20% of total borrowed volume and 8.2% of all borrowing transactions during the period.

This strategy amplifies exposure when markets move favorably but creates catastrophic vulnerabilities when they turn. The paper found that liquidations occurred in concentrated waves, with just four assets—Wrapped Ether (WETH), Wrapped Staked Ether (wstETH), Wrapped Bitcoin (WBTC), and Wrapped eETH (weETH)—representing 90% of total liquidated value.

The Real Cost to Borrowers

The Bank of Canada study quantifies what borrowers actually lost during major liquidation events. Liquidation fees alone typically ranged from 5% to 10% of liquidated value. But when researchers factored in missed gains from subsequent price recoveries, combined borrower losses reached 10% to 30% in some cases. These aren't theoretical numbers—they represent real capital destroyed when market volatility triggered forced exits.