The Holy of marketing Holies, your brand, is no longer a guarantee for the future, according to a provocative report in the New York Times. The article focuses on AT&T, but offers an important look into one of the most dangerous trends in American business today — relying on brand until it’s too late.

Famous brands have faded before, of course, but the impact of deregulation, galloping technology, marketing clutter and increasing global competition has made it harder than ever for established brands to stay on top. That is especially true when a dominant player in a market fails to react to change, allowing new and aggressive rivals to innovate with products or pricing.

No one is suggesting that brands are not important. But increasingly, marketing experts say, companies that think their brands will insulate them against competition are in for a shock. The reverse is more likely to be true, marketers say: the brand will not compensate for missteps, but missteps will devastate the brand.

The increased competition in many industries underscores the new reality that few brands can be all things to all people. “The metaphor for American society is no longer the melting pot; it’s the quilt,” Mr. Donatiello (Nicholas Donatiello, president of Odyssey, a San Francisco research firm) said. “People no longer want to watch the same television show or use the same toothpaste.”