Sturgeon's Law says that 90% of everything is crap. Although he was originally expressing the sentiment with regards to a macro-level of art (i.e. 90% of films are crap, 90% of books are crap, etc.) I think it also applies at decidedly more micro-level as well. Meaning that 90% of everything you or I produce is crap.
Obviously, crap is relative here. If 90% of what I make is crap, but I always produce something better (or worse) than the next guy, then a strict definition of crap would mean 100% of his (or my) output is crap. What I'm saying, though, is that 90% of what I make is crap only when compared to what I make. The next guy might be infinitely better or worse than me, but his stuff is still 90% crap... relative only to the broader body of work he produces.
With that in mind, then, it makes sense, as a creative individual, to create as much as you possibly can so that the 10% of your work that isn't crap is enough to make a living on. And, if you're extremely talented or incredibly lucky, some of your non-crap work will even find it's way up to the 10% of non-crap work overall.
But here's the other thing: the 10% of your non-crap work changes over time. You don't just create 10% of your life-long awesomness when you're 20 and produce nothing but crap for the rest of your life. By the same token, you don't produce crap exclusively until you're 60 and suddenly come up with your 10% of non-crap. No, 90% of what you've made by the time you're 20 is crap, and 90% of what you've made by the time you're 60 is crap. Some of that latter crap may well include things that were part of your 10% non-crap work from when you were 20!
You ever look at something you created years earlier? An old drawing or a poem or whatever? You thought it was absolutely fantastic at the time but, now, 5... 10... 20 years on, it looks like crap. That's what I'm talking about. In fact, if your older work doesn't look any worse to you now than it did before, then you haven't really grown or improved in the intervening time.
Now, if you took a decade off from painting to focus on raising your kids (or whatever), obviously your painting skills wouldn't improve over that time, and your older paintings probably look just as good to you now as they did then. That's perfectly reasonable, I think. But once you get back into painting, you should start improving again (once you've gotten past whatever level of atrophy your skills fell into) and you should soon see your older work as crap.
Everything is changing all around us. Technology, of course, but also the way we interact with the rest of the world. Twitter didn't exist ten years ago, and internet-connected cell phones were quite the rarity. But not only do they exist now, but they've changed the face of how we think and act on a day-to-day level. How much of your Twitter stream got filled up with election day coverage on November 6? That wasn't a news feed like you might see scrolling across the bottom of CNN; that was running commentary shared by your friends and acquaintences from around the country, if not the world. That was you and hundreds, if not thousands, of loosely connected individuals having a large group discussion in real time about an event that was going on throughout the country. Ten years ago, you could do something approximating that with a dozen or two people in a chat room or message board. Twenty years ago? Almost unheard of. You sat in a room, and any discussion was limited to the people in that room. Maybe one or two people on the phone line. The technology has enabled a fundamental change in how we operate as a society.
And if the art you create isn't reflective of society, it's more likely to be seen as a failure. That is, it's more likely to be seen as crap. The implication here is that it's becoming harder and harder to create art that's not crap, and that the improvements that you used to see in your work are potentially less relevant/important. Meaning that your more recent work is going to be less likely to supplant your previous work, and your window for creating additional non-crap gets smaller instead of larger. After all, how many comic creators do you know that made something fantastic in their 20s or 30s, and have produced nothing of any particular note since?
I might be full of crap with this. This post could well be part of the 90% of my work that is crap. But I tell you, this is the kind of stuff that scares me personally. For whatever insignificant level of relevance I have here and now, how much less do I have to look forward to because I can't keep up? I'm certainly going to try to fight that notion as long as I can, but mankind as a whole does not have a good track record in that department.
Here's hoping this post is part of my 90%!