Why do successful companies fail when the business climate changes? Some say it’s because companies become paralyzed with fear and do nothing.

But Donald N. Sull says that’s most often not the case. On the contrary, says Sull, a faculty member at Harvard Business School, the problem isn’t that companies do nothing. It’s that they do nothing different.

If a company has become successful based on a certain perception of its market, it doesn’t stop and reevaluate. If it’s developed processes that have proven effective over time, it turns them into unalterable routines. If it’s built a winning culture with a particular value set, those values become corporate dogma.

As a result, Sull says, leaders often refuse to rethink core practices and strategies, even when the business market is in upheaval. Though they may see a threat coming from a competitor or from a major market change, they don’t change course. Instead, they simply paddle harder, believing that the winning formula that worked before will work again. It’s the corporate version of “dance with the one that brung you,” only with more fervent commitment than you’d get from any prom date.

Sull calls this phenomenon active inertia. In "Why Good Companies Go Bad," an essay published by Harvard Business Review, Sull examines how active inertia led to the downfall of such former leading corporations as Firestone and Laura Ashley. Though the paper was published four years ago, its advice remains timely. In a book schedule for release in May, "Revival of the Fittest: Why Good Companies Go Bad and How Great Managers Remake Them," Sull provides the rest of the story, revealing what can be done to overcome corporate inertia.