The European Union has a strategic policy of maintaining a stance of ambivalence on many different issues. Among them, it has managed to keep the countries of the Western Balkans on hold, without clarifying what their prospects for accession to the bloc may be or what kind of timeframe they may be looking at.
What this is, effectively, is a weakness. And it is also one that constantly reignites tensions in a part of the world that is already on tenterhooks. It is a shortcoming that adds one more layer of insecurity and instability to an environment of widespread geopolitical turbulence.
As far as Greece is concerned, it has a vital interest in its neighbors being put firmly on the path to EU membership soon.