Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happens if a debtor pays back its debt? Is that money consequently getting "erased" again (just like it's been created)? What happens if a debtor defaults on its debt? Does that money then just stay in the economy, impossible to drain out? What is the general expectation of the central banks? What percentage of the debt is expected to default and how much is expected to be paid back?
And specifically in the case of central banks buying govt. debt: Are central banks considered "easier" creditors than the public? What would happen if a country defaults on a loan given by a central bank? Would the central bank then go ahead and seize and liquidate assets of the country under a bankruptcy procedure to pay off the debt (like it would be standard procedure for individuals and companies)?
I'd love to see this properly explained, because it definitely has a counter intuitive ring to me.
I'm pretty ignorant in this field, and usually I've been a day or so behind the posts (missing the window to press for more information), but I feel like there's definitely some contention there.
So sure, the loaned money might still be in the system in some naive sense, but value has been destroyed in the asset price? Suddenly a lot less money buys a lot more asset and that's where we find the deflation.
If I borrow 1M for an asset in good times and can't pay it back, the creditor gets the asset and probably gets a good portion of that 1M back. If that same scenario plays out in bad times and my whole street defaults on the same asset at once, there's a resulting fire sale and far more value is destroyed (including being wiped off neighbouring, non-creditor-owned assets of the same type) than money added by leaving the loan sloshing around somewhere else in the economy.