Greece loaned too much, collected too little taxes (or rather, scamming the tax man was and is an integral part of daily life there) and had extremely generous pension plans and ages.
They hired Goldman Sachs to hide all this by cooking the books so they could join the EU.
I have zero sympathy for the Greek and 'destroying a country for the decisions made by the elite doesn't count when you vote for those castle-in-the-sky promising elite year after year.
Greece it's bill was simply due, and the myth of 'poor little Greece bullied by stringent North Europe' needs to die.