What scenarios are DAI and USDC each suited for in DeFi? When should you choose which one?
Both have clearly different optimal use cases in DeFi:
Prioritize DAI when: you need censorship-resistant stablecoins and don't want any centralized institution having the ability to freeze your assets (Circle has the ability to freeze specific USDC addresses; DAI's smart contracts have no equivalent blacklist mechanism); you're using protocols that accept DAI as collateral but limit or don't accept USDC; you value decentralization principles and are willing to bear the capital efficiency loss from over-collateralization.
Prioritize USDC when: you need the broadest protocol support and liquidity (USDC is nearly ubiquitous across major DeFi protocols); you're doing cross-protocol capital movement where USDC's liquidity pool depth is larger; you need fully compliant, auditable assets (institutional DeFi scenarios); your operations are frequent and USDC's on-chain operations are simpler than DAI Vault management.
Use both when: Curve's stablecoin liquidity pools (3pool includes DAI, USDC, and USDT) — simultaneously holding all three lets you provide liquidity in the same pool, capturing fees from multi-stablecoin demand.
How do MakerDAO's governance token MKR holders benefit from DAI's operation? Is there a risk of conflicts of interest?
Both MKR's value capture mechanism and potential conflicts of interest are worth understanding.
MKR's benefit mechanism: The MakerDAO system collects Stability Fees from borrowers (similar to interest). After deducting operating costs, excess revenue is used to buy back and burn MKR in the market. As MKR supply decreases, each MKR theoretically becomes more valuable. Additionally, if the system adopts RWA (Real World Assets) as collateral, related interest income flows into the system, ultimately benefiting MKR holders.
Potential conflicts of interest: MKR holders' voting interests don't always completely align with DAI holders' interests. For example: MKR holders may lean toward accepting higher-risk but higher-yielding collateral (like riskier RWA or crypto assets) because this increases system revenue, ultimately benefiting MKR value. But if such collateral encounters problems, losses are primarily shared by DAI holders (through under-collateralization risk) and MKR holders (through dilutive new minting).
Implication for DAI users: DAI's decentralized governance is an advantage, but it isn't neutral — governance participants (primarily large MKR holders) have their own interest considerations. Understanding this lets you more objectively evaluate MakerDAO's governance decisions.
What impact did the 'zero-bid auction event' (Black Thursday 2020) have on MakerDAO's liquidation design? How was it fixed?
The March 12, 2020 event was MakerDAO's most important stress test in its history, exposing critical flaws in the liquidation mechanism and driving significant design improvements.
What happened: ETH dropped 50%+ within hours, the Ethereum network became simultaneously congested (gas fees spiked), and normal liquidation bots couldn't submit bids in time. Some liquidation bots seized the opportunity to bid 0 DAI (zero) for collateral ETH and successfully won auctions, causing approximately $6 million in unrecoverable losses for MakerDAO (collateral taken at near-zero cost while DAI debt remained unpaid).
How MakerDAO responded: Emergency vote to mint new MKR, auctioned on the market to raise DAI and fill the gap (MKR holders bore the loss); updated liquidation mechanism (upgrade to Liquidation 2.0), introducing 'Clip' auction mode with minimum reserve prices to prevent zero bids; added liquidation buffers providing more buffer time before auctions begin; raised minimum collateral ratio requirements for some high-risk collateral types.
Lessons for current DAI users: The current liquidation mechanism is much more robust than in 2020. But the combination of 'extreme market + on-chain congestion' remains an inherent risk for any system based on on-chain liquidation mechanisms. If you're using DAI with higher leverage, maintaining sufficient collateral ratio buffer is a safer strategy than relying on the liquidation mechanism to 'work normally.'
What is Sky Protocol? What significant changes happened after MakerDAO's rebrand?
In 2024, MakerDAO underwent a major brand and architecture restructuring, renaming and reorganizing the entire protocol as Sky Protocol, with several accompanying changes:
Major change 1: Stablecoin restructuring. Sky Protocol launched a new stablecoin USDS (positioned as an upgraded version of DAI), while retaining DAI for continued circulation as the legacy version. Both can be exchanged 1:1, but USDS was designed with a feature MakerDAO had previously avoided: freezable addresses (similar to USDC's blacklist function). This design aims to comply with potentially future regulatory requirements, but critics argue it compromises the core principle of decentralized stablecoins.
Major change 2: Governance token split. The MKR token was renamed SKY, at a rate of 1 MKR = 24,000 SKY, while retaining legacy MKR in continued circulation. This design aims to lower the governance token's unit price to attract more small holders to participate in governance.
Impact on existing DAI holders: if you hold DAI, no action is currently required — DAI continues circulating normally, exchangeable 1:1 with USDS, but won't automatically convert. If you want to benefit from USDS's DSR (savings rate), you can actively exchange. If you value DAI's 'decentralized and no-blacklist' characteristics, you can continue holding DAI. Currently both circulate in the market with similar functionality — the main difference is in their regulatory compliance orientation.
DAI is a strange creature in the crypto world: it's a stablecoin with no centralized issuer; it maintains a dollar peg, but its reserves are volatile crypto assets. The mechanism behind this 'how is that possible' is simultaneously one of DeFi's most elegant engineering achievements and the best case study for understanding why decentralized stablecoins necessarily have limitations.
As of 2026, DAI (whose underlying protocol is now called Sky Protocol, formerly MakerDAO) has approximately $5 billion in circulation — the largest decentralized stablecoin. Understanding its mechanics gives you a more complete understanding of the entire stablecoin design space.
The answer: over-collateralization.
You deposit $1,500 worth of ETH, and the system allows you to borrow 1,000 DAI. That $1,500 in collateral is the safety buffer for 1,000 DAI — even if ETH drops 30%, the collateral is still worth $1,050, still enough to cover 1,000 DAI's face value.
This design solves the problem of 'issuing dollar-equivalent stablecoins without having dollars' — the reserves aren't dollars, but over-collateralized crypto assets. Under normal conditions, the collateral's value always exceeds the DAI borrowed, so the entire system remains solvent.
The cost: extremely low capital efficiency. The same amount of money used in a fiat-backed stablecoin system works 1:1; in the DAI system, you need to lock in 1.5x or more assets to borrow the equivalent DAI. This makes DAI difficult to scale rapidly.
In MakerDAO (Sky Protocol), each user's borrowing position is called a Vault. You deposit collateral and lock it in a Vault, and the system calculates the maximum DAI you can borrow based on your collateralization ratio.
Using ETH as an example (minimum collateral ratio 150%): if you deposit 3 ETH at $2,000 each (total $6,000), the system allows you to borrow at most 6,000 ÷ 150% = 4,000 DAI. But most users borrow less (like 3,000 DAI), maintaining a higher collateral ratio (200%), to avoid triggering liquidation from small ETH price drops.
The fee for borrowing DAI is called the Stability Fee — MakerDAO's primary revenue source, equivalent to a borrowing interest rate. The Stability Fee is determined by MKR token holder governance votes, currently around 5-8% annualized (varying with market interest rates).
Liquidation is the critical defense line for the DAI system's solvency. When your Vault's collateral ratio falls below the protocol's liquidation threshold (like ETH's 150%), the system automatically auctions off your collateral to repay your borrowed DAI, charging you a liquidation penalty (typically 13%).
Liquidations are executed by Keepers — automated programs operated by third parties that monitor all Vaults approaching the liquidation line 24/7, submitting transactions to capture liquidation opportunities the moment conditions are met, receiving a portion of the liquidation penalty as compensation.
The liquidation mechanism's design assumption: when collateral is pushed to market, there are always enough buyers willing to purchase at a fair price, allowing the system to recover sufficient funds. This assumption holds in normal markets; on Black Thursday in March 2020, ETH dropped 50%+ within hours, and liquidation bots couldn't execute in time due to spiking gas fees, resulting in approximately $6 million in bad debt for MakerDAO — the 'zero-bid auction event,' where liquidation bots won large amounts of ETH at near-zero cost.
DAI's peg mechanism is fundamentally different from USDC's arbitrage redemption mechanism — more complex and more fragile.
When DAI is above $1: arbitrageurs open new Vaults, borrow DAI, sell it at above-$1 market prices, and profit. Large numbers of arbitrageurs increasing DAI supply → price falls back to $1. Simultaneously, MakerDAO governance can lower the Stability Fee, reducing borrowing costs to incentivize more DAI borrowing, increasing supply.
When DAI is below $1: arbitrageurs buy DAI at below-$1 prices to pay off their own Vault borrowings, redeeming collateral at a discount and profiting. Large numbers of arbitrageurs reducing DAI supply → price recovers to $1. Simultaneously, governance can raise the Stability Fee, increasing borrowing costs to suppress supply.
Another important tool is the DAI Savings Rate (DSR): if DAI is below $1, governance raises the DSR to attract users to lock DAI into savings contracts for interest, reducing circulating DAI supply and pushing the price up.
This mechanism is effective under normal conditions, but it relies not on 'a guarantee to redeem 1:1 for dollars,' but on the assumption that 'arbitrageurs are willing to participate under any conditions.' In extreme markets with dried liquidity, this assumption may not hold.
MakerDAO initially only accepted ETH as collateral. The 2019 upgrade to a multi-collateral system (Multi-Collateral DAI) now accepts: major crypto assets (ETH, WBTC, stETH, etc.); centralized stablecoins (USDC, USDP); some RWA (Real World Assets, like tokenized US Treasury products).
Accepting USDC as collateral is controversial — it compromises DAI's 'fully decentralized' characteristic, since USDC is a centralized asset issued by Circle. If Circle freezes specific USDC addresses, related DAI collateral would be affected. This is an important detail for understanding 'decentralized stablecoins aren't entirely decentralized.'
MKR is MakerDAO's governance token — holders vote on all key parameters (collateral types, minimum collateral ratios, Stability Fee, DSR, etc.). MKR simultaneously serves as the system's 'last resort': if the system accumulates bad debt (collateral insufficient to cover borrowed DAI), the system automatically mints new MKR to auction on the market, using the DAI proceeds to fill the gap. After the 2020 Black Thursday event, MakerDAO covered the $6 million in bad debt through exactly this MKR auction mechanism.
Conversely, if the system has surplus profit (Stability Fee income exceeds operating costs), excess DAI is used to buy back and burn MKR on the market, giving MKR deflationary characteristics. This is MKR's value capture mechanism.
Understanding DAI's mechanics lets you more accurately judge which scenarios it's suited for — and which it isn't. DAI's core advantage is decentralization and censorship resistance — if you need a stablecoin that cannot be frozen by any centralized institution and you're operating in DeFi, DAI is the most mature choice currently available. Its core disadvantages are low capital efficiency (requires over-collateralization) and liquidation risk (requires active collateral ratio management).
For most ordinary users with cross-border payment goals, USDC's simplicity and liquidity advantages are clear. But if you're deeply engaged in DeFi, have higher decentralization requirements, or are concerned about censorship risks with centralized assets, DAI is worth adding to your toolkit. The prerequisite for using DAI is genuinely understanding collateral ratio management and liquidation mechanics — using it without understanding it is the biggest risk of all.