H269 maintenance.
In Ivor's case it may have been the maintenance facility as to the reason why the 300's he operated seemed to always be in the hangar.
Yes you do get some dog aircraft but from my experience the 300 has always been pretty damn reliable, however, I have flown good aircraft that have faults that can only be blamed on poor maintenance.
Don't forget an aircrafts reliability has a lot to do with the owners willingness to spend money and the organisation that maintains it.