Have you flown them more than once???
My last three flights with them:
2001: ATH-TXL. They couldn't find enough crewmembers for a morning flight from their main hub! Resulted in a 3-hour delay and me missing my connecting BA flight and meeting in BHX!
2001: ATH-SKG. The 2pm flight was delayed enough to be departing after the 4pm flight. Took my money over to Axon (RIP) for a very enjoyable flight.
2002: IOA-SKG. No problems, although service was, erm, spartan (still it was a 50 minute flight on an ATR so my expectations hadn't been high in the first place).

I go to Greece 4-5 times a year, and always avoid OA like the plague.