Way back when, Greece was a bumbling, but no more so than many places, small country. It had allowed far too many people to hold government jobs, it promised fat pensions to all sorts of people, and it allowed massive tax evasion.
Each year the government found it was paying out far more than it was taking in with taxes. And back in those carefree days before the Euro, Greece made payroll by simply printing Drachmas as needed. This caused the Drachma to sink on the foreign exchanges, but no body really cared much.
Then Brussels invented the Euro. International currency, run by the Germans, and solid as the US dollar. Lots of prestige for countries allowed onto the Euro. And, the Greeks wanted to go on the Euro for the coolness and the prestige of it. They begged and pleaded and cooked their books to look more solvent than they really were. And the Europeans let the Greeks into the Euro, mostly 'cause they all felt sorry for the struggling Greeks and didn't want to slam the Euro door on them.
Well, now when the payments exceeded tax revenues, Greece could no longer print the necessary money. Now they had to borrow the shortfall from banks. And Europe was full of sucker banks, who would loan money to Greece, thinking that a Euro country was good for it, and even if they weren't, the IMF or the ECB, or someone would guarantee the loans. Whereas any one of any sense would see that the Greeks were never gonna make enough money to pay the loans off. Sucker banks have no sense.
Sure enough, a few years go by, and Greece cannot make payments on the loans. And for no good reason the IMF bailed them out in 2010, and again in 2015. Each bailout came with firm instructions to cut expenses ("austerity"). Each time the Greeks failed to cut much. And now the Greeks are broke, business is terrible, unemployment is way up, things are bad, and the Greeks are blaming it all on the lenders.
What should have happened, back in 2010, instead of a bailout, the Europeans should have just let Greece sink. That would have caused Greece to default on her loans. And after a default, even sucker banks are not going to make new loans. The money would have gone away, and the Greek government would have had to lay off a lot of government workers, and start collecting its taxes. And the Europeans would have saved them selves a lot of grief and ill will, not to say a lot of money.