So, in the long run, Greece needs to leave the Euro. Except, a majority of Greeks want to stay in the Euro. Thus, the current Greek government wants to get kicked out, so they can blame the EU for it. But the EU does not want to take the blame, so they won't kick out Greece. What we have now, is a slow speed train wreck.
The part of the story I find interesting, that nobody is talking about, is that there are no written procedures for either kicking Greece out of the Euro Zone, or for Greece to voluntarily leave the Euro. One side or the other would have to unilaterally declare their action, and then dare the other side to deal with it. There will be 8000 lawsuits in 30 different courts asking judges to essentially create the rules as they go. Those cases could drag on for years. The financial markets would hate that kind of uncertainty.
Nah, the problem is more that leaving the Euro is effectively impossible unless your economy is stronger than the Eurozone average, whether they want to or not. Currently everybody in Greece have their income and accounts in Euros, and those with a choice would continue to keep it that way, as any new currency would only be introduced to be devaluated, so no one would WANT the new currency, and only the poorest could be forced to use it. If most of the economy would continue to operate in Euros because no one wanted the new currency, then changes in the value of new currency would have no effects on the economy. And being useless the value of new currency would hyperinflate.