I wasn't suggesting all anoraks, just maybe people with the intelligence to get themselves some sort of experience working in aviation prior to applying be it FISO, PPL or being an ATC cadet or even just cleaning aircraft.
Many years ago my intake was virtually 50/50 new entrants and ex assistants; we started with 23, by the end of the 4 week initial course we were down to 22, and after 3 years training in all aspects getting all civil ratings, we graduated with 16. As far as I recall, we 'lost' most of them during the aerodrome field training.
How many courses nowadays graduate that proportion of 'starters'? Often they combine 2 courses graduating at once so as to make it look as though there's a lot of successes.