This article originally appeared on LinkedIn.

At the start of the year, how many of you resolved to lose weight? And how many of you have actually dropped some pounds?

If you did lose weight, I bet you’ve been tracking your calories, exercise and weight fastidiously. That’s because countless studies indicate that people who weigh themselves regularly and keep food and exercise diaries are better at managing their weight.

I would argue that philosophy applies to meeting nearly every goal in life, from saving for your first home to keeping stress in check. One of the best pieces of advice I ever received came from my uncle, a world-class physicist who later became a business executive. My uncle and his wife graciously took me in for seven years while I was a student and just starting out in my career. He liked to remind me that until you can measure something, it’s hard to get better at that thing. Learning (and most of science) depends on reliable measurement.

I took this notion to heart, but I always wondered how I could apply it to the “softer” issues in business (and life), such as the emotional aspects of customer and employee behavior. How do you measure the delight of a customer who walks into a store angry but leaves with smile, or the vague frustration of an employee who doesn’t have the authority to fix a customer’s problem? How do you measure the loyalty of an employee who goes the extra mile to help his team delight customers?

These things have huge implications for the bottom line (and quality of life). Some executives mistakenly think that financial metrics drive their business, but a company’s success is truly defined by how many lives the company enriches and diminishes. As corny as it sounds, success is about people, not numbers.

Management legend Peter Drucker famously said, “If you can’t measure it, you can’t manage it.” Most executives probably hear this maxim on their first day of business school if they haven’t heard it already. But how do you measure interactions and relationships—lives enriched and lives diminished?

It only took me three decades of working closely with companies to figure it out. I was in my 50s when I conceived the Net Promoter Score® and System®. More than half of the world’s large companies now use NPS® to measure and manage the quality of relationships they are building with customers and employees. Their goal is to grow, but they’re actually measuring their employees’ ability to help enrich the lives of their fellow human beings. When it applies the Net Promoter System to its internal processes, a company tracks its ability to meet its employees’ need to make a real difference in the lives of teammates and customers.

Most leaders want their customers and employees to be happy. In a social media world where it’s so easy to complain publicly, companies have more tea leaves to read than ever. So when a company can tap into the true feelings of its people—customers and employees—then the real work can begin.