$143. That, by Southwest Airlines’ own account, was all that was left in its bank account in the spring of 1972.
Its president, Lamar Muse, had one move left: sell the fourth of its four Boeing 737s. The sale brought a $500,000 profit and one more shot. But to keep the schedule with three planes, each one would have to be in and out of the gate in 10 minutes. Most airlines took an hour.
“We can,” said Bill Franklin, the vice president of terminal operations. “And we will.” He told his ground crews that anyone who couldn’t do a 10-minute turn would be fired, and so would the next person, until the company found someone who could.
When Michael Porter explained the answer, 24 years later, much of it was a list of things Southwest didn’t do.
What Southwest didn’t do
A turn meant more than 100 tasks. So the hostesses, as flight attendants were then called, and often the pilots tidied the cabin themselves instead of waiting for cleaners. There were no assigned seats. Passengers grabbed what they could, and as soon as the door closed the plane was pushed back. The crews didn’t always make 10 minutes, but often enough for it to become the company’s signature.
In 1996, when Porter made Southwest the centerpiece of “What Is Strategy?” in the Harvard Business Review, the turn took 15 minutes. Well-paid crews under flexible union rules were part of the answer, he wrote. “But the bigger part of the answer lies in how Southwest performs other activities. With no meals, no seat assignment, and no interline baggage transfers, Southwest avoids having to perform activities that slow down other airlines.” The speed was built out of refusals.
The hard part of strategy is choosing what not to do. “The essence of strategy is choosing what not to do,” Porter wrote. A trade-off, in his definition, means that more of one thing requires less of another. An airline can serve meals, which adds cost and slows the turn at the gate, or it can skip them, “but it cannot do both without bearing major inefficiencies.”
A hiker who wants to move fast leaves the tent and the cooking pot at home. Pack for every kind of trip and you carry all of it, at a walk.
Continental Airlines tried to pack for both. It launched Continental Lite to match Southwest on some routes, with no meals and faster turns, while staying a full-service airline everywhere else, with travel agents, a mixed fleet, baggage checking and seat assignments. Lite planes got held at the gate by baggage transfers. Late flights and cancellations brought a thousand complaints a day. Cheap tickets couldn’t carry standard agent commissions, so Continental cut commissions on all its flights. The results, in Porter’s words: “angry travel agents and full-service customers.” The airline lost hundreds of millions of dollars, and the CEO lost his job.
The more IKEA set itself up for buyers to carry and build their own furniture, Porter wrote, the less it could serve customers who wanted more service.
When the trade-off is fake
Porter didn’t claim every trade-off is real. A company far behind the best practice of its day can often get cheaper and better at once, the way manufacturers who adopted rapid changeovers in the 1980s managed to lower cost and improve differentiation at the same time. Those were “false trade-offs.” Near the frontier, he wrote, the trade-off between cost and differentiation is “very real indeed.”
Others go further. W. Chan Kim and Renée Mauborgne, the authors of blue ocean strategy, argue that a company creating new market space can “break the value-cost trade-off.”
The finance director’s request
Imagine you run a five-person IT help desk that promises a person on the line within ten minutes. The finance director wants a technician on her floor every morning.
Say yes, and you’re down to four people on the phones every morning. Nobody decides to break the ten-minute promise. Callers just start waiting fifteen, then twenty.
Say no, and she may complain upstairs. So you write down what the desk doesn’t do, desk visits included, and what it offers instead: a screen-share within ten minutes. When the complaint comes, you have a page to show.
The cheap agent that matched the humans
AI can look like the end of this choice. In February 2024, Klarna said its AI assistant, live for a month, was handling two-thirds of its customer service chats and doing “the equivalent work of 700 full-time agents,” with customer satisfaction on par with human agents. It estimated a $40 million profit improvement that year.
In May 2025, according to Bloomberg, chief executive Sebastian Siemiatkowski said his pursuit of cost-cutting in customer service had gone too far. “As cost unfortunately seems to have been a too predominant evaluation factor when organizing this, what you end up having is lower quality,” he told Bloomberg, as Fortune quoted him. He was planning to recruit people so that customers would always have the option of a real person.
The trade-off hadn’t gone away. It had moved, to which errands and which customers get a person. Before switching a service to AI, write down the promises you’re keeping, such as a person reachable within a set time, and track those apart from the cost line. Then read a sample of the AI’s closed conversations against what each customer needed.
Eight million simulated boardings
On July 25, 2024, Southwest said it would assign seats. Its research, it said, showed that 80 percent of its customers, and 86 percent of potential customers, prefer an assigned seat, and that open seating was the top reason customers gave for switching to a competitor.
It said it had run over 8 million simulated boarding trials and was confident the change would not compromise its operational efficiency. It set assigned seating to start with flights on January 27, 2026. In 1996, Porter had named no seat assignment as one of the things that let Southwest turn its planes fast. Now the airline was giving it up, and saying its operation would hold up without it.