When I was a little kid, the old retired guys who let me hang around while they were reloading would allow us to learn by sorting and prepping brass. They got free labor and we got a free education. It was Win-Win because later on you got to do some shooting too.
Talk about making a silk purse out of a sow's ear...
Even the GOV's surplus brass was a tedious job best done by little fingers with young eyes.
All of it was awful compared to what we can get today.... but... it taught us many things including how to process junk into the best it could be.
You saw some pretty awful commercial brass from factory ammo back then. High thickness variations, off-center flash holes, material defects, etc., and you couldn't count on a brand name to stay the same year after year. With some Mi-Surp dating back several wars, even that had to be inspected very closely, but on average it was decent.
Of course the difference in those days was how much easier it was to get government surplus brass and range brass with fairly good odds of sorting it to find enough of a single headstamp.
While we can buy much better quality brass these days, younger folks are not being exposed to as much GOV surplus and ranges are far less likely to give up their brass if it is any good. We have it much better in many ways with brass quality, but in other ways the shortages have ruined the advantage.