[sharkmerry]

> I'm assuming these stable coins aren't actually backed by $150bn in actual USD,

Maybe I am missing something, how is this different than banks employing fractional reserve banking?

[gizmo686]

Several differences:

1) Fractional reserve banking has caused numerous financial crisies.

2) In the US, banks are required by law to carry deposit insurance (FDIC). While it is theoretically possible for the FDIC to become insolvent, that is far less likely than a bank becoming insolvent. Further, in practice, the FDIC can't fail because the government will just fund it directly if it's actual funds ran out.

3) While banks have less cash on hand than the sum of their debts; they are still solvent. That is to say, they are capable of paying back all of their creditors, they just need to be able to collect from their debtors in order to afford it.

When a bank takes a deposit for $100, they have a $100 liability, and a $100 asset in cash. Net worth $0, technically solvent.

They then loan out $90. Considering the likelihood of repayment, interest rate, and loan term, this debt is an asset that is worth (hopefully) >$90, so the bank remains solvent. The bank can take some of that surplass worth they have to do things like pay salaries, build offices, fund FDIC, give executive's their bonues, etc.

In contrast, when a stablecoin takes a deposit of $100, they have a $100 liability and $100 asset in cash. If they take $90 to pay salaries, they now have only $10 dollars in assets and are insolvent. In theory, a stablecoin could loan out that $90, or use it to invest is something else. If they do this, they are in roughly the same situation as the bank where they are hoping that their asset ends up being worth as much as they expect. They are also less regulated then banks, so the odds of something going wrong (either mallisiously or not) is greater.

In practice, even the normal banking system runs into some issues:

* Deposits into banks are much more liquid then loans out of banks. In theory, everyone can decide to withdraw all their money tomorrow. But if you took at a mortgage, the bank may have to wait 30 years to be fully payed back. This can be mitigate by selling debt to other institutions, or taking out loans backed by the debt, but you can still run into issue when these markets experience problems.

* Debtors do not always pay back what they owe to the banks. In theory this is accounted for, but if banks overestimate the actual value of the debts, they can end up in a situation where they are actually insolvent.

[tata71]

> if banks overestimate the actual value of the debts, they can end up in a situation where they are actually insolvent.

I think everyone here knows they'd never do that!

[spiralx]

Banks don't lend out deposits though - a $100 loan creates both a $100 liability - the value in the customer's account - and a $100 (plus interest) asset - the loan itself - which also balances out to $0. The process literally creates money, meaning a bank could theoretically lend money even if it had no deposits at all. The constraints on making loans come from central bank requirements and regulations, not deposits made.

The fractional reserve model makes sense for commodity-backed money or things such as stablecoins that are backed 1:1 in some way, just not for banking in the modern economy where physical money is only a small part of the money supply.

https://www.bankofengland.co.uk/-/media/boe/files/quarterly-...

[dnadler]

That's not a great analogy, you can't redeem currency at a bank.

My understanding is that stable coins are stable because they claim to be backed 1:1 by some other currency. If they are not actually doing that, then thats a fraudulent statement, isnt it?

[CryptoPunk]

Not all stablecoins claim redeemability for USD. Some claim each unit's redeemability for an amount of some digital asset that is worth 1 USD, with the amount redeemed fluctuating in proportion to the value of the digital asset, to maintain the stable value.

[Nasrudith]

And all of the incentives are set up for the maintainer to take the money and run. Excessive ammounts of idle money is an attractive nuisance.