"Iconic brands like Apple, Starbucks, Harley Davidson, Patagonia, and Herman Miller have at the core of their DNA a mythic storyline that inspires the actions, beliefs and behaviors of its devoted tribe members over the long term."

The trick is (and it's damn-near impossible) to come up with a storyline that's timeless and never gets old. THAT'S the ultimate challenge.

The problem is simple: stories come to an end.

Is it really the case where a brand (and its mythical storyline) is indefinitely sustainable, or is it more like a play that opens, has its run, and finally closes? 

One could argue that that apex of the brand equity curve has been reached by all of the companies mentioned in your post. Sears' came decades ago; Starbucks doesn't have nearly the weight it once did. Apple's brand equity may have peaked on the very day Steve Jobs died.

So while we might not think of Apple as a brand in decline (yet), how does Apple's "mythic story" evolve to invite new members into the tribe? Is it even possible? Can they stay on the forefront of their brand position (insanely great paradigm-shifting technology with simplified UI's)? Probably not. The brand story can be promoted and retold again and again, but at some point, it requires that they deliver. Again. And again. And again. 

Is Sears' fate ultimately the same as Apple's? I'd argue it's far more likely than not.

A particularly fascinating example is Harley Davidson. Their core (and truly authentic) market left a long time ago. Their existing base, while still large, is aging and younger potential customers generally want nothing to do with Harley. That mythical storyline (of rebellious bad-ass freedom) just doesn't play anymore -- at least not to younger audiences. And in some ways, the very people who bought into the brand story and promise were the same ones who unknowingly killed it. Middle-class, overweight, old middle-managers may certainly embrace their own inner bad-asses, but it's a tough sell to the next generation.  

Without a doubt, HD has done a remarkably great job of getting an audience to adopt its brand and "lifestyle," but it's in a heap of trouble because the story doesn't resonate anymore. It's sort of like "Cats" on Broadway: Once a cult hit, then acclaimed, then unbelievably hot, then huge, then in decline, then essentially dead.  

Even with an incredible story, how many times can you watch the same movie?

Very thought-provoking post. Thank you!