Aave is a decentralized lending protocol that lets users lend crypto assets to earn interest, or borrow against collateral, without a bank or credit check — one of the largest and longest-running DeFi lending platforms, and a useful reference point for understanding how on-chain lending actually works.
Key Takeaways
- Lenders deposit assets into shared liquidity pools and earn interest paid by borrowers, with interest rates adjusting algorithmically based on supply and demand.
- Borrowers must post collateral exceeding the value of what they borrow (‘overcollateralization’), since there’s no credit check or identity verification in a permissionless system.
- If a borrower’s collateral value falls too close to their loan value, it can be automatically liquidated to protect lenders — a mechanism enforced by smart contracts rather than a human loan officer.
- Aave has introduced features like flash loans (uncollateralized loans that must be borrowed and repaid within a single transaction) used primarily by developers and traders for specific technical strategies.
- As with any DeFi protocol, funds are exposed to smart contract risk — a bug or exploit in the protocol’s code, distinct from the risk of a borrower defaulting.
Our Take
Aave’s overcollateralization requirement is the structural answer to a specific problem permissionless lending can’t avoid: without credit checks or legal identity tied to a loan, there’s no way to pursue a defaulting borrower through traditional means, so the system instead requires borrowers to post more collateral than they borrow, letting automatic liquidation protect lenders instead of a legal recovery process.
This is a fundamentally different trade-off than traditional lending: it means DeFi lending like Aave’s is capital-inefficient for borrowers compared to a bank loan (you generally can’t borrow more than you’ve posted in collateral), but it also means the system works without any identity verification, credit history, or geographic restriction — a genuine trade-off between accessibility and capital efficiency that traditional and decentralized lending resolve in opposite directions.
FAQs
Why does Aave require more collateral than what you borrow?
Since there’s no credit check or legal identity verification in a permissionless system, overcollateralization and automatic liquidation are how the protocol protects lenders instead of pursuing defaulting borrowers legally.
What is a flash loan?
An uncollateralized loan that must be borrowed and repaid within a single blockchain transaction, used primarily by developers and traders for specific technical strategies like arbitrage.
📎 Source: Learning Heroes — Aave Criptomoneda: ¿Qué es y cómo funciona?
