rsu,
I don't agree that they're the throwaways of aviation.
Sure, they might not have cracked AN or QF, or even mightier, CX etc., but missing out doesn't mean that were never good enough; just not good enough on the day, i.e., there were applicants with more desirable quals and experience in the batch they went through with.
The airlines are full of people who were just good on the day.