I got an email from Alexey Eromenko pointing out that I really sort of ignore another common way to hyperinflation.
If a central bank is trying to peg the local currency to a foreign currency even while printing new money they can lose too much of their reserves and not be able to hold the peg. At this point the currency can suddenly crash and they can get hyperinflation.
In general I am focused on Japan, the UK, and the USA. These countries are big and seem headed for hyperinflation. These guys don't peg to anyone else, so I have not thought about it much.
However, Alexey is correct that a currency peg has been an issue in some case. In Argentina's case the government basically stole the reserves of the central bank. Using the Real Bills view of hyperinflation, we can see that this, or even losing all your reserves trying to defend a peg, should lead to hyperinflation.
I suspect that it is going to turn out to be true that much of the time this happens the government was running a large debt and deficit. So the central bank was trying to help out the government with new money, but then ran into trouble defending the peg. So in some sense it is very similar in origin to others. If a central bank is running a proper currency board they would always be able to defend a peg to the other currency.
But my idea of the typical start to hyperinflation is the central bank monetizing bonds and people fleeing bonds. The central bank has to keep buying bonds because the government has a huge deficit and needs cash to operate, so there is a huge flood of new money. The peg route to hyperinflation is different from this. Something worth keeping in mind.