system
Given the following post, respond as if you're commenting on Reddit:
human
Why is the Euro collapsing? It seems like such a good idea for all of Europe to share a currency.
gpt
A single currency allows for more efficient trade, but removes monetary policy from the individual nations and gives it to the bank of the entire EuroZone.

As everyone is using and borrowing the same currency, when some countries *cough Greece cough* lie about their finances to get in and then do a terrible job on their own economy, it hurts their currency which is also the currency of everyone else in the Eurozone. This makes it harder for other countries to borrow money, which hurts their economies, and makes it even HARDER for the others (and those initial countries) to borrow money, etc. etc.