This article originally appeared in LinkedIn.

How do we measure greatness? Last week Apple became the first company in history to reach a market capitalization of $1 trillion. Does that mean it’s great?

In Western societies today, the measure of greatness of a business or an individual seems most often measured by their financial net worth.  

But look at a list of historical figures of lasting greatness like Socrates, Jesus, Gandhi, Lincoln, Einstein, Mother Teresa, Mandela, Jonas Salk or Martin Luther King Jr., shows the common trait is not wealth, but impact. These people improved the lives of many.

Maybe a better measure of greatness than financial net worth is the number of lives you enrich—net of those you diminish.  

While Apple Stores don’t have the same historic stature, enriching the lives of customers has been their central mission since the beginning. All employees in the stores and contact centers are encouraged to focus on enriching customers’ lives. The company gathers feedback to determine what percentage of customers feel so good about their experience that they would enthusiastically recommend Apple to friends or colleagues.  Apple was one of the earliest adopters of the Net Promoter Score® and Net Promoter System®. 

When you touch someone’s life and have such a positive impact that they give you an unqualified recommendation that they would want their loved ones to have a similar experience—this is clear evidence you made their life better. With daily feedback provided by Apple’s rigorous Net Promoter System directed to their employee smartphones, living the Golden Rule of treating others as you would like to be treated—striving toward greatness—is approaching a scientific reality. 

This was echoed after we launched our last book, The Ultimate Question 2.0, when my coauthor Rob Markey and I convened a group of CEOs from highly regarded Net Promoter pioneers, companies like eBay, Charles Schwab, Intuit and Rackspace, to learn more about their experiences.

These leaders were utilizing Net Promoter® not simply as a tool for measuring customer loyalty, they were utilizing it as a practical moral compass for their organization. As former Rackspace CEO Lanham Napier said: “There are plenty of measures of ‘bigness’ but very few measures of ‘greatness,’ and we want to be great. NPS® is our ‘GPS’—‘Greatness Positioning System.’ ”

Rather than a geographic destination, Net Promoter helps companies target greatness. Apple’s $1 trillion market cap may just be the evidence that it is working.  As long as Apple maintains the highest Net Promoter Score in its industry, its future will remain bright. Because when customers feel their lives have been enriched, they come back for more and bring their friends. This is what makes a company great.

Net Promoter®, Net Promoter System®, Net Promoter Score® and NPS® are registered trademarks of Bain & Company, Inc., Fred Reichheld and Satmetrix Systems, Inc.