The concept of the euro, might seem a failure, but in reality it succeeded in enslaving many european countries by converting their debt (in national currency) to ...externally issued currency/external debt. This chained these countries into slavery*.

Any country that does not have serious trade surpluses to achieve bigger euro inflows than outflows (debt repayments+interests) is practically doomed.

** I've analyzed this in an older article of mine: https://steemit.com/money/@alexgr/why-the-euro-is-a-scamcoin