There are many people who are convinced that the main reason for the high F104 loss rate in the Luftwaffe was the rapid expansion of that air force. If overnight one tries to grow too quickly one ends up with a relatively inexperienced cadre of air and groundcrew. Add an aircraft much more advanced than they had before in large numbers and with some distinctly dangerous handling characteristics and you can sit back and count the losses.
In the USAF Luftwaffe training programme there were also losses - several in the mid-70s due to flap problems. However, the RCAF operated the aircraft with great success and a low loss rate.