The definition of success was "earned a living wage" but some were much more successful than that. I was thinking about this particular issue recently because a good friend, one who falls squarely into the "should have quit" category, has recently become homeless.
> Was it clear to you or even to most people? In what way was it clear, why? I'd expect the ones with more business acumen to "make it" as artists.
It was clear to most people. The best way I've seen the feeling described is the scene from The Sopranos when Hesh says: "There's good and there's not good ... Talent is talent ... a hit is a hit" [0]. The point is, you can recognize talent, but that doesn't mean you can necessarily articulate what makes it good. There is something tautological about taste: it's good because it's good.
> I don't know about neutral observers. Successful artists often make kitch that sells. Would you say Vincent van Gogh failed in his artistic pursuits?
Most people aren't Vincent van Gogh.