I've taught two. It was a one on one sort of deal, and a few years apart.
One kept at it because he was a tight wad. He quit reloading when I told him it was time to buy his own equipment.
The other was a competitive shooter and it let him make better ammo. It made his hobby more affordable, and his scores were better.
Others were interested, but when it came time to put away the beer, sit down, actually learn, and do it:
They just never quite made it over.