The Wall Street Journal last week had the latest in what have been a string of stories this season about slumping CD sales. In this piece, "Still Recording After All These Years," writer Ethan Smith took the tack of looking at the disappointing sales of one-time superstars. He writes that fans of these artists -- Paul McCartney, Stevie Wonder, Neil Diamond and the Rolling Stones among them -- want to hear the classics, the hits. No matter how good their latest releases are -- and all four have well-reviewed new discs in stores -- they just aren't selling. "Such middling results are unwelcome news for the beleaguered global music business, where banks on the fourth quarter for as much as 40 percent of its revenue," he writes.

Though the piece did offer some interesting sales figures, which I'll get to in a moment, what it really could have used is some analysis. It's not news to report that music isn't selling. What is needed is for someone to say why it's not selling. Let me offer a theory. First, most of what is released today is simply dreadful. Again, that's not news, but it gets to the heart of why music fans have little loyalty. Second, the work these career artists released in between their last significant hits and their current hoped for renaissance was really dreadful. Third, the people who are fans of these artists long ago stopped looking for new music from them. They want the hits they grew up with and that's pretty much it.

Add it all up, and it doesn't matter how perfectly the geriatric artists mentioned above have recaptured their past glory (and let's be honest, they're close but nowhere near back in hit-making form), there is nobody there to buy it. Most people form their music listening habits in high school and college. If they buy music as adults, it is music that approximates that sound, or better yet, repackages that same music. It's why the new Greatest Hits package from John Fogerty (which for the first time includes most of his biggest Creedence Clearwater Revival hits) has sold half the number of discs as Paul McCartney's new disc in a third of the time (159,000 since November compared to 337,000 since September): People want familiarity, and the real thing sells better than a close approximation every time.

So, you have artists who once could be assured of selling millions now hoping a little sales bump at Christmas will give them a gold record. The antidote, of course, is beyond their grasp. They needed to have made consistently good music over the course of their careers so that they could keep old fans and continue to make new ones. U2 is a good example of this, a band with only one real stinker in its back catalog (Pop). R.E.M., given its spotty recent work, seems to be on track to be one of those bands that makes a stirring return to form every few years or so with decreasing impact on the charts.

In the Journal article, XM DJ George Taylor Morrison talks about the latest from Big Star, included in the article for no good reason (the band was never popular and no one save for a few of us uber-power pop geeks was pining for new product): "I still think they could have spent a little more time on this one," he says about the profoundly disappointing disc In Space (of which he is apologetically supportive). That's good advice for all artists in today' rapidly shifting marketplace, fair or not: Don't stumble too often, because your fans might not stick around to help you up.