The ongoing Greek drama – it has been downgraded from a full-blown crisis – came about when the opposition refused to support the government's nominee for president for the third time, triggering a general election in January which was won by Syriza, at the head of a “radical coalition of the left”. They didn't exactly sweep to power, but did garner enough seats to form a coalition government which aimed to remove the “troika” from Greek affairs; slash the debt mountain by half (by getting the IMF and the Eurozone to pick up the tab); restore Greek dignity, ending the “humanitarian crisis” and get Germany to stump up a preposterously large sum in war reparations.
Prior to the fall of the outgoing government, the IMF and the Eurozone were on the cusp of disbursing the final tranche of €7.7 billion under the second bailout. Greece was arguing that it would not need a modest, third bailout as it would be able to meet its obligations through savings and a return to the money markets (Germany thought a further €10 billion was probably needed) and the country had posted a small economic surplus (later disputed). Things were on track.
For the vast majority of outsiders, the Syriza manifesto pledges were a simple wish list and about as likely as a visit from a jolly old man in a red suit that spends much of his year at the North Pole. Syriza was granted an extension to their bailout of three months to come up with what their creditors would see as viable plans for the nation's economic future. This time was frittered away and all that was seemingly achieved was the irritation and frustration of Greece's partners and creditors.
Beyond the hour for agreement (showing how keen Eurozone members were to see the bloc remain as a whole) negotiations were being held until the Greeks abruptly called a referendum, asking their citizens to reject further austerity – which they did. The “no” vote would trigger a deal within 48 hours and allow the banks to open within 24 hours, Syriza told the people. Rather than the “no” vote causing a crisis amongst the other 18 Eurozone states which would have them pleading for an accord on Greek terms, it suddenly became clear to Syriza that their partners were making plans for a Grexit (they never did explain how such a vote would magic enough money into Greek banks that they could open within 24 hours, of course. In the event, they stayed closed for a further 2 weeks). Eurozone leaders didn't even discuss the matter until the Wednesday after the Sunday vote.