There are a number of differences between military flying training and that found in the civilian world, and in the "chop rate" simply because the requirements are quite different.
I'm not claiming that military pilots are superheroes. However, there is a large difference in the ability and capacity levels required to fly for recreation in a simple, single engined helicopter and those required of a military pilot flying a large, complicated helicopter full of troops or weapons, at extremely low altitude and high speed, into a tactical situation - especially so in poor weather conditions or by night. Similar for those abilities required to operate an Anti-submarine or Search and Rescue helicopter.
It should be remembered that even to get selected for a military flying training scheme, a candidate will have undergone close scrutiny during a highly competitive selection process. Not everyone has the mix of abilities required, it's a plain fact, or there would be a NIL drop out rate and no need for a selection process.
Someone has pointed out that military training is at the taxpayer's expense. Because of this, the training system HAS to provide the best pilot product for the money and it is very much geared to avoid failure at a late stage, when the training becomes considerably more expensive per hour (and a very large amount of public money will have been invested). Military students are only given a small amount of flex hours, especially in the very early stages of training, before their continuation on the course is put under formal review.
Certainly in my time, a student was immediately considered for review if a trip was failed (i.e. didn't perform to the required levels of the syllabus, which is laid out for the instructor in writing). He would refly the trip, probably with a different instructor or flight commander. If this was also not up to the standard required, he would be formally interviewed, told why he was on review and given a small number of hours (5?) while his overall performance was reviewed. If it was unsatisfactory, he would be required to fly with the Chief Instructor, which was sometimes the student's last trip in the system (the dreaded "Chop Ride").
Civilian flying schools operate under a quite different regime to this. While the instruction given at most is very good indeed, it has to be borne in mind that they do exist to make money by providing a service to a paying customer. They therefore have the flexibility to accommodate the requirements of a much wider spectrum of abilities.