Say 200 - 250 hours to go through basic and advanced flying training - that leaves 200 hours of 'experience' before training as an instructor. That would be very unusual in the British Military RW world but 'Creamy' FW pilots are often taken straight out of the training system to become QFIs.
Perhaps the German Army has a similar system to the 'Creamy' one - they are called creamy's because they are supposed to be the cream at the top and are skimmed off.
In my experience many are p*ssed off because they get left behind in the training system while their (theoretically not so able) mates go on to front-line.