Yeah I think Qantas has the intent to hire every cadet, but they have also given themselves a safety blanket just incase a crap cadet somehow got through their application process (no process is perfect).
I believe they had the same deal with maintenance apprentices a few years ago - no guarantee of a job at the end of their training... what happened there?
Back in the 80s QANTAS offered cadetships where they paid the training and you had an obligation of a return of service and repay this debt from your salary. There was a minimum age (20 y.o) - I was 19. I asked to be considered but was told "Come back next year - we'll have the same offer then". That was the last year of sponsored cadetships.
I went on to get my PPL however all the doom and gloom stories made me decide to pursue a career in IT and keep the flying as a hobby. I haven't flown for a few years (usual story - marriage, mortgage, family etc) although I should be in a position to start again this year. After hearing that the maximum age for QANTAS pilots (direct entry and cadets) is gone, I might give it a go again. Or, I might get an instructor rating and instruct part time...