That is, it's better to produce 100 things and throw away 99 than it is to sit around a perfect 1. In the end the quality will be higher.
http://russelldavies.typepad.com/planning/2007/02/quantity_e...
Over the course of of a session, when you're jamming with your synthesizers and instruments, a project can transform from A to B to C to D to E where E ends up sounding nothing like A. You have your hard- and software synths, fantastic effect plugins and hardware, drum machines, more outboard gear. You tweak and compress, change melodies and harmonies. You press 'save as a new version' every minute.
Your wandering mind be damned, if you want a great track you need to stop, sit down, and focus. All good tracks I come up with come from a focus on quality, not quantity. By the way, in my opinion, iterative refinements do not belong into the category of "quantity", I don't know how anyone could make such a statement.
Of course you sometimes need the sessions to come up with some idea that resonates with you, but after that you (read: I, I'm talking about my own experience) have to force yourself to focus.
My best work is actually a culmination of these "snippets" that I build up over a few months/weeks. It's like with each mediocre/average project I produce, I'm discovering the parts of the great one not too far off.
It's the same thing with code, design and all my other creative projects. I have to wade through a lot of weaker ideas and designs in order to discover the best parts. And once I figure those out, it's mostly a rewrite of all my past ideas into the one good idea.
How are Jobs' keynotes so well delivered? Repetition, iteration, practice, just like martial arts, makes perfect.
Shockingly there's more to art than a trite truism. If you want to acquire skill, go for quantity. But after that, if you want to become a master, if you want to impact people's lives in a way they appreciate and care about you'll need more than skill, you'll need inspiration.