Economist often cite the hyperinflation in Germany in 1921-23 as an example of why you don't want money printer to go brrr. But that's not the whole story. The terms of the London payment plan made the Mark basically a toxic asset. It wasn't simply that there were a lot of them.

The terms of the plan seem designed to make the Mark worthless. Germany had to pay the reparations in gold and foreign currency, and they were pegged to the value of German exports. The need for Germany to buy foreign currency to pay the debt drove its price up relative to marks.

Basically, you have marks, you owe x amount to France under threat of invasion, but they refuse to take marks and want francs. Obviously francs rise in price relative to marks.

And then you get the meme of "wheelbarrows of cash to buy a loaf of bread" This is because in 1923 France invaded and occupied the Ruhr, a major industrial hub and German workers went on strike, leading to shortages all over the country. Add that to the already falling mark.

And then suddenly, for no reason at all...

The real lesson is that crippling war debt, being forced to buy foreign currency to pay the debt, international (((speculators))) treating your currency like cancer because of these conditions and then major shortages due to an invasion and strike = hyperinflation.