What it means
A traditional loan involves a bank checking your details, holding the money and enforcing the contract. In DeFi those roles are replaced by published code: a borrower locks up digital assets as collateral, the contract releases a loan, and if the collateral falls too far in value the contract sells it automatically.
No one approves the transaction and no one can reverse it. Most DeFi lending is overcollateralised, meaning you must deposit more value than you borrow, often 150% or more.
That sounds strange until you realise the system has no way to check identity or chase a defaulter, so the collateral is the only protection it has. It also explains why DeFi has not displaced ordinary business lending, which depends heavily on knowing the borrower.
For finance teams the practical relevance is usually indirect. A treasurer may need to understand DeFi because the company accepts digital assets, because an acquisition target holds them, or because auditors ask how such balances are valued and controlled.
Even businesses with no involvement often field questions from boards curious about what the technology does. The risks are unusual rather than merely large.
Code errors have drained hundreds of millions of dollars from contracts that appeared sound, transfers to a wrong address cannot be recovered, and there is no deposit protection or ombudsman to appeal to. Regulatory treatment is still developing in most countries, so today's compliant activity may need reworking tomorrow.
Advertised returns deserve particular scepticism. Double digit yields generally compensate for real risks: the volatility of the underlying token, the chance that a contract fails, or rewards paid in a newly created token whose value can collapse.
Treating those numbers as comparable to a deposit rate is the fastest route to a painful loss.
In practice
Real-world examples.
Example
A software company is paid $250,000 in a stablecoin by an overseas client and must decide how to hold it. The finance director converts it to dollars the same week, judging that the accounting and custody complexity of holding it outweighs any yield on offer.
Example
An investment committee reviewing a fund allocation asks how the manager's 14% advertised return is generated. The answer, that most of it comes from newly issued governance tokens rather than borrower interest, changes the committee's view of the risk entirely.
Example
A trader borrows against digital collateral to fund a purchase and is liquidated overnight when prices fall 25% while markets in her time zone are closed. The automated contract sold the position without warning, because that is precisely what its code was written to do.
Think of it
“DeFi is finance on blockchain without banks-financial services run by code.
Formula
Calculation
The core calculation in DeFi lending is the collateralisation ratio: collateral value / loan value, expressed as a percentage. Liquidation happens when this ratio falls below the level the contract requires.
A borrower deposits digital assets worth $15,000 and takes a stablecoin loan of $10,000. The collateralisation ratio is $15,000 / $10,000 = 1.5, or 150%.
If the contract liquidates any position that falls below 120%, the minimum collateral value the borrower can sustain is $10,000 x 1.20 = $12,000. That means a fall of $15,000 - $12,000 = $3,000, or 20% of the collateral's value, triggers automatic sale of the assets, which in volatile markets can happen within a single day.Case study
Seen in the real world.
The following is an illustrative, fictional example. Northgate Analytics, an invented data consultancy, agreed to accept payment in a widely used stablecoin from a client that found international bank transfers slow and expensive. The first payment of $180,000 arrived in minutes rather than the usual four days.
The interesting problems came afterwards. Northgate's fictional board had to decide who held the wallet keys, how a payment would be reversed if a client sent the wrong amount, and how the auditor would confirm the balance at year end. It ended up writing a short treasury policy: convert to dollars within two business days, require two approvers for every transfer, and hold no more than $50,000 in digital assets at any time.
A junior manager separately proposed depositing idle cash into a lending contract advertising 11%. The board declined after establishing that the return depended on a reward token created by the platform itself, and that no protection existed if the code failed. The consultancy kept the payment speed benefit and left the yield alone.
Watch out
Common mistakes.
- Treating an advertised DeFi yield as comparable to a bank deposit rate, when the two carry entirely different risks and no protection scheme stands behind the first.
- Assuming transactions can be reversed or disputed, when a transfer to a wrong address is generally permanent and unrecoverable.
- Confusing decentralised protocols with centralised digital asset exchanges, which do hold customer funds and can fail in a much more familiar way.
Questions
People also ask.
Do businesses need to account for digital assets differently?
Yes, most frameworks treat them as intangible assets or as inventory rather than as cash, which changes both valuation and disclosure.
Is DeFi lending cheaper than bank lending?
Rarely for a normal business, because the collateral requirement of 150% or more makes it unsuitable for anyone who needs capital they do not already hold.
What is a smart contract audit?
An independent review of the code before release, which reduces but never eliminates the chance of a flaw that allows funds to be drained.
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