In 1979, Howard Putnam, CEO of Southwest Airlines at the time, faced a complex problem and a difficult decision on the new direction to steer his company. 
The deregulation act passed in 1978 opened the gates for a flood of new competitors in the airline industry, leading to a drastic fall in fares.
But this would only be the beginning of a wave of uncertainty and disruption for airlines.
From 1972 to 2002, just about every bad scenario you could think of crippled the airline industry: fuel shocks, strikes, recessions and the 9/11 terrorist attacks.
In the early 1990s alone, the airline industry lost nearly 13 billion dollars, high profile airlines went bankrupt and hundreds of thousands of workers were laid off.
And yet, despite the chaos, Southwest Airlines did not lay off a single employee.
In fact, over the 30-year period, not only did Southwest Airlines generate profits each year, but it also performed 63 times better than the general stock market. 
The puzzling question then is: Why did Southwest Airline survive and thrive in an extremely complex, uncertain and disruptive environment and other companies didn’t?
The Power of Upper Limits
In the book, Great by choice: uncertainty, chaos and luck—why some thrive despite them all, strategy researcher, Jim Collins, reveals Putman’s final decision to:
“Do the same thing that you are already doing well…and do it over and over again.” 
Unlike their competitors, Southwest Airlines set upper limits on their business growth and had the discipline to turn down opportunities.
For example, in 1996 alone, over 100 cities begged for Southwest airline services, but they only chose to work with four. 
Despite being a publicly traded company, Southwest was willing to sacrifice growth for the sake of maintaining a high level of performance and customer service.
In addition, Southwest set upper limits on how the business operated.
These included, flying only 737 planes, providing no food services and no interlining.
These upper limits were specific, actionable, and most importantly, sustainable over decades.
Now, compare this to how we typically set goals and plan to achieve them.
We often begin by setting goals with lower limits, but no upper limits of what we can sustain i.e I plan to read at least 5 books each month, write 1,000 words a day, workout four times a week and generate 100,000 dollars in revenue.
But then, once we’ve hit the goal—even though we couldn’t sustain it—we set a bigger goal, which eventually leads to complexity, overwhelm and failure.
If instead, we set goals with upper limits, it becomes much easier to figure out what’s truly important to focus on and stick to our goals over the long run.
If your goal is to build a profitable business that lasts, your upper limit could be a maximum of 10 clients each year and 50 employees.
If your goal is to improve and maintain a high level of performance at work, your upper limit could be a maximum of 7 working hours each weekday and none during the weekends.
If your goal is to get and stay in shape, your upper limit could be a maximum of 3 workout sessions each week.
By setting upper limits to your goals, you’ll not only solve complex problems quicklyand make better decisions, but you’ll also maintain high levels of performance and achieve long-term success, no matter the level of chaos and uncertainty around you.
Do Only What You Can Sustain
We live in a world obsessed with “stretch goals,” quick results and fast growth.
We want more. We want it faster. And we want it now.
But the Southwest Airlines story is one of many examples to remind us that in the long run, bigger and faster isn’t always better.
And more often than not, slow and steady wins the race: it pays to stick to doing only what you can sustain and nothing more.
It is only those who can resist the temptation to add more to their plate when times are good, that will ultimately survive and thrive when times are bad.
When in doubt about how to set your goals, ask yourself this question: can I sustain this for the next 10 years?
If the answer is no, create an upper limit that will turn your answer into an emphatic yes.
This article was originally published on mayooshin.com.
Mayo Oshin writes at MayoOshin.com, where he shares well-researched ideas based on science, philosophy and art, for better productivity, creativity and decision-making. To get these ideas to think and live better, you can join his free weekly newsletter here.
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