I recently came across an article about "On-Chain Fixed Interest Rates," which pointed out a very practical judgment:

Most on-chain funds still prioritize the ability to withdraw at any time over the interest rate itself.

The real demand for fixed-rate lending mainly comes from borrowers—such as institutional borrowers and cyclical strategy users—who need a certain financing cost;

But from the perspective of the fund providers, the vast majority are unwilling to accept a fixed term for a slight interest rate premium. Once lenders are required to sacrifice flexibility, the interest rate becomes unsustainable.

This is also why the truly large-scale on-chain markets are still those like Aave, which offer variable interest rates and flexible deposit and withdrawal.

From this perspective, DeFi at this stage truly needs only three things:

1⃣ Funds can be entered and withdrawn at any time
2⃣ Interest rates do not fluctuate wildly
3⃣ Can support a continuously expanding scale

Only by maintaining flexibility and stabilizing lending rates does the subsequent structure make sense.

Within this framework, @sparkdotfi's positioning is actually perfectly aligned.

Many people may have already noticed that the issuance of USDS has surpassed 10 billion USD.

The significance of this milestone is not in the number itself, but in the fact that it enables Spark to provide long-term stable financial/lending rates.

Relying on USDS as a scaled, low-volatility capital base, Spark can, while maintaining the experience of flexible deposits and withdrawals, buffer short-term supply and demand shocks through liquidity management, allowing lending rates to remain within a slowly changing, predictable range during expansion.

Currently, the observed interest rate volatility ranking is: Spark (lower) < Aave (medium) < Morpho (higher)

So from the perspective of that article, what Spark is doing is actually a necessary step before scaling up lending—

Making interest rates sufficiently stable, affordable, and scalable.

In DeFi, as long as this foundational layer exists, those who truly need fixed interest rates can lock in costs through interest rate swaps, without forcing all funds to sacrifice liquidity.