What Greece needs is a mix of debt forgiveness, market reform (labor market and otherwise) to unfreeze a sclerotic economy which is more about bribing the bureaucracy than actual competitiveness, and a measure of austerity (starting with a later retirement age, and going from there). They were starting to go down that road! They made real progress with economic growth during the recovery! But the reforms were unpopular and might be impossible to do with their internal politics, leading us to the current crisis.
So instead they're going to do the alternate version of hard-and-mean austerity by replacing euros with worthless drachmas and making everyone poorer (hope you don't owe money in Euros). Then they'll either rot for a while in stagnation before gradually getting their act together after all, or they'll turn to Vladimir Putin for bailouts from the great petro-state as long as they last (with all the relevant geopolitical consequences and "screw you Europe" strings attached).