First, spot the similarities. Over time, the strategies of incumbents tend to converge. A useful exercise is to overlay the business models of companies in the same industry and then look for areas of overlap. Wherever you see competitors doing the same thing, ask yourself, “What’s the shared assumption behind this policy or practice?” and then, “What would happen if we challenged that belief?” For centuries, innkeepers assumed you had to own rooms to offer guests a bed for the night. Airbnb inverted this belief and now has more than six million listings across the world.

Second, focus on what hasn’t changed. What aspects of your strategy have remained stagnant for years or decades? Over time, legacy practices, like wallpaper, become invisible. Your job is to question whether those 12 13 taken-for-granted practices still make sense. For example, though it endured a lot of pushback from traditional carmakers, Tesla challenged the long-held practice of selling cars through independent dealers. The company’s sleek stores, often located in luxury shopping venues, offer customers a hassle-free buying process. Tesla understands that the best orthodoxies to challenge are those that degrade the customer experience.

Third, go to extremes. Pick some parameter of performance—price, choice, availability, speed—and ask what would happen if we aimed for a 10X improvement? Fifty years ago, a retired physician, Dr. Govindappa Venkataswamy, launched an epic quest to eradicate unnecessary blindness in India. Millions of his compatriots had cataracts but couldn’t afford corrective surgery. How, Dr. V. wondered, could he reduce the cost of surgery by 90 percent or more? For inspiration, he looked at the fast-food industry. “If McDonald’s can sell millions of burgers,” he thought, “why can’t [we] sell millions of sight-restoring operations?” Today, Dr. V.’s network of specialty hospitals, the Aravind Eye Care System, performs half a million cataract surgeries annually.

Leslie Hannah, an eminent business historian, has shown how the ‘rationalisation’ of industry, which was favoured by the British Government (represented by the Bank of England), set the stage for the new ‘corporate economy’ which would characterise Britain for decades. The 1920s saw the creation by merger of ICI (chemicals), the Distillers Company (Scotch whisky) and Unilever (soap and margarine). A similar wave of mergers in Germany established IG Farben and Vereinigte Stahlwerke as the dominant chemical and steel producers respectively. (Both these companies were dissolved by the victorious Allies in 1945.)

Here's the trick for incumbents: the experiences we just described feel very different to consumers, but they share lots of back-end processes. The Best Buys and Armanis of the world can compete with players that are more focused, because the two companies gain certain advantages by linking multiple models together. In other words, each service model in the company somehow makes the other service model better off. In Best Buy's case, for example, two distinct models share one location (a very tricky thing to pull off), which achieves economies of scale on real estate.

And this story repeats itself through the history of management science; almost every classic of the literature seems to have described a way of adapting systems to a more complicated world, and then to have become obsolete itself. If you look past the slogans and think about what things like ‘management by objectives’, ‘focus on core competences’ and so on actually mean, they are all different ways of advising executives to restructure their businesses so that they don’t generate complexity faster than it can be managed.

Here's the trick for incumbents: the experiences we just described feel very different to consumers, but they share lots of back-end processes. The Best Buys and Armanis of the world can compete with players that are more focused, because the two companies gain certain advantages by linking multiple models together. In other words, each service model in the company somehow makes the other service model better off. In Best Buy's case, for example, two distinct models share one location (a very tricky thing to pull off), which achieves economies of scale on real estate.