It is buried in this piece about the German finance minister. (He wanted to show Greece the door.) The real reason is vanity. Schäuble Pushed for a Grexit and Backed Merkel into a Corner – SPIEGEL ONLINE.
Had it been up to Schäuble, Germany would have shown the Greeks the euro-zone door long ago. His problem, however, is that the chancellor doesn’t share this sentiment. Merkel rejects his insistence because she doesn’t want to go down in history as the government leader responsible for the disintegration of Europe.
She is supposed to do what is right for Germany. But she choose to do what will make her look good in the long run. Or what she hopes will look good in the long run.
And for those of you not up on European cabinet ministers…
Moreover, Schäuble enjoys a special place in Merkel’s cabinet. He has been a member of German parliament, the Bundestag, since 1972; he served under Helmut Kohl as interior minister and party leader; and he negotiated the reunification treaty in 1990. Shortly thereafter, he was shot and crippled by a mentally ill man. Schäuble isn’t simply a politician, he’s a piece of German history, and therefore untouchable. He even has the chutzpah to threaten Merkel with his resignation should she force him to act against his convictions.