That's rarely the fault of the crew, though management may like to have people believe that's the case. EK typically enter a market with daily services, on the other hand QF seem to think a few a week will do the trick. The crew sit around waiting for the next service to lob up. European services are typically constrained by curfew requirements at each end. Having said all that, QF's fleet utilisation is absolutely miserable and management seem to believe that having aircraft sitting on the ground is good for business, part of their "cost saving" brilliance by not having them in the air costing money to run I suppose. But it typically doesn't come down to crew, at least not unless you consider insane and blatantly unsafe 2 man crewing hours used by some airlines.