Lending and Borrowing Money With No Bank in the Middle
Decentralized finance recreates lending, borrowing, and trading using code on a blockchain, with no bank or broker. It removes the middleman and replaces trust in institutions with trust in code, for better and worse.
Finance Without the Institutions
Decentralized finance, often called DeFi, recreates financial services, lending, borrowing, trading, earning interest, using automated code on a blockchain rather than banks, brokers, or other intermediaries. Instead of depositing money at a bank that lends it out, a user interacts with code that automatically matches lenders and borrowers, holds the collateral, and enforces the terms, all without a company or institution in the middle.
The core idea is removing the intermediary and replacing trust in institutions with trust in code. Where traditional finance relies on banks and brokers to hold money, enforce contracts, and manage risk, DeFi relies on code, called smart contracts, to do these things automatically. This removes the middleman and their fees, and it replaces the protections of regulated institutions with the risks of relying on code and operating in a volatile, largely unregulated environment.
A bank stands between lender and borrower, taking a cut and providing trust. DeFi replaces the bank with code, removing the cut and the middleman, and also removing the safety net the regulated institution provided.
How DeFi Lending Works
In DeFi lending, users deposit cryptocurrency into a pool governed by code, and borrowers take loans from the pool, with the code automatically managing the process.
| Element | How it works |
|---|---|
| Lenders | Deposit crypto into a pool, earn interest |
| Borrowers | Borrow from the pool, post collateral |
| Collateral | Usually more than the loan, held by code |
| Enforcement | Code liquidates collateral if needed |
A distinctive feature is overcollateralization: borrowers must post collateral worth more than the loan, since the code cannot assess creditworthiness or pursue a borrower who defaults, so it relies on holding excess collateral it can seize. If the collateral value falls too far, the code automatically liquidates it to repay the loan. This makes DeFi lending different from bank lending, since it cannot lend based on trust or credit assessment, only against collateral it holds, which limits who can borrow and how, but allows lending without any institution assessing or trusting the borrower.
The Appeal
DeFi appeals for several reasons. It removes intermediaries and their fees, potentially offering better rates by cutting out the bank margin. It is open and permissionless, letting anyone with crypto participate without approval, which appeals to those excluded from traditional finance or wanting to avoid it. And it is transparent, since the code and transactions are visible on the blockchain, unlike the opaque operations of banks.
The vision is a financial system that is open, transparent, and free of intermediaries, where anyone can access financial services through code without needing permission from or trust in institutions. This appeals to those who value the openness, the removal of gatekeepers, and the transparency, and who are willing to accept the risks in exchange for a system that operates without the institutions and their control. The appeal is genuine, offering a different model of finance, though whether it delivers on the vision or mainly serves speculation is debated, and the risks are as significant as the appeal.
The Risks
DeFi carries significant risks that come with removing the institutions and their protections. The code can have bugs or vulnerabilities that attackers exploit to steal funds, and there have been many large hacks and exploits, since the code holds the money and a flaw can be catastrophic, with no institution to make users whole. The volatility of crypto collateral means positions can be liquidated suddenly, and the largely unregulated environment offers little protection or recourse when things go wrong.
The replacement of trusted institutions with code means the code must be correct, since there is no backstop if it fails, and the history of DeFi is full of exploits, failures, and losses from code vulnerabilities, scams, and the collapse of projects. The lack of regulation means no deposit insurance, no recourse, and little protection, so users bear the full risk. These risks, code vulnerabilities, volatility, and the absence of the protections that regulation and institutions provide, are the cost of removing the intermediaries, and they have caused enormous losses, making DeFi a high risk environment where the removal of institutions removes their protections along with their fees.
The Bottom Line
Decentralized finance recreates lending, borrowing, and trading using code on a blockchain rather than banks and brokers, removing intermediaries and replacing trust in institutions with trust in code. DeFi lending works through pools governed by code, with borrowers overcollateralizing since the code cannot assess creditworthiness, and it appeals through removing fees, openness, and transparency. But it carries significant risks, code vulnerabilities that enable large hacks, the volatility of crypto collateral, and the absence of the regulation and institutional protections that traditional finance provides, so the removal of the middleman removes the safety net along with the fees, making DeFi a high risk environment that offers a different model of finance at the cost of the protections institutions provide.