Prudie and Spikeybush have, perhaps unwittingly, identified the problem.
Germany, in particular, will not allow the value of the Euro to fall. It suits them to have a strong currency and the structure of the Eurozone is designed almost exclusively for their economy (and to a lesser degree that of France). The lesser Eurozone nations have been reeled into the scam that is the Euro. They have borrowed huge sums - far more than they could ever be expected to repay - at interest rates far below those they would have paid had they kept their own currencies. (Those interest rates were “Euro-wide” rates, designed to suit Germany). Germany did very well out of this by selling goods and services to those countries who used their cheaply borrowed money.
Now the chickens have come home to roost. Those countries have now become so indebted that it has become (very belatedly) apparent that they must either be “bailed out” with taxpayers’ money or they must go skint. This would not have occurred had they retained their own currencies. Firstly, they would not have been able to borrow such huge sums and the cash they did borrow would have been at considerably higher interest rates. Secondly their currencies would have devalued as their debts increased helping them attract inward investment and sell more of their goods and services as they became cheaper with the devaluation of their currency. That is what variable exchange rates are for.
The Euro was a flawed project from the outset. And the most annoying thing of all is that the politicians who pressed on with it (and in particular allowed the weaker nations to flout the entry criteria in order to join) were warned that the precise circumstances that now prevail were a strong possibility.
They ignored those warnings and pressed on. And everybody is now paying the price for their vanity and folly.