The previous Greek FinMin was Stournaras. A more buttoned-up friend of Varoufakis's, one who actually gave Varoufakis his first job. Being demure got the Greeks nowhere. Varoufakis and Tsipras actually achieved a small measure for Greece, which was largely because of Varoufakis's big mouth.

Plus, the Greek people really like the duo, and that will be THE most important thing going forward.

There are only two reason for Tsipras to change Varoufakis:

1. Jealousy of V's popularity
   
2. Change to a FinMin in favor of Grexit.