There is an entire industry devoted to helping companies determine customer satisfaction levels through surveys and analysis. But how much real value does knowledge of "satisfaction" contribute to helping you keep profitable customers?

The answer, unfortunately, is "not much." Though surveys do serve a purpose (primarily showing trending: "Are we doing better or worse than last year?"), they don't tell the whole story.

The following are three fundamental reasons why it's dangerous to rely on customer satisfaction surveys to help improve your Customer Experience:

1. Dissatisfied customers don't speak up

Yes, some customers respond to satisfaction surveys, but which customers? Using which channels—online, phone, mail, email? Scary as it might sound, recent studies show that for every 100 dissatisfied customers only two bother to say anything to the company; the rest "vote with their feet" and just leave.

If you think about it, this makes sense. If you're unhappy as a customer, do you try to remedy the situation or "fix" the company? Isn't it easier to just say "to heck with it" and leave? Of course, that doesn't mean that customers don't tell others about their bad experience. In fact, research shows that customers share bad-experience stories with approximately 15 people (mainly other prospective customers), while those with good experiences share their stories with only seven people or so.

2. Customers won't tell you the truth

In many cases, when customers do respond to satisfaction surveys, they indicate that they're "satisfied" or "mostly satisfied" regardless of how they really feel. A study of people who recently left their bank illustrates this point: 80% responded that they were "satisfied" with their former institution. Of course some people leave a bank because they move or for some other valid reason―but not four out of five.

Why such disparity between words and actions? Simply put, it's easier. Also, the notion of "satisfaction" is a very soft concept. What does satisfied mean? For most, it indicates meeting expectations. Human nature is to be "nice"; so if things aren't great, but not horrible, that usually equates to "satisfaction." Therefore, satisfaction is definitely not a good indicator for customer loyalty.

3. Even if customers want to tell you the truth, they can't, because they're irrational

Customers are sensitive, emotional, and, let's face it, irrational beings. How do we know this? Because research indicates we're all emotional irrational beings, and in recent years we've learned just how irrational.

Shockingly, 95% of our brain activity centers on the irrational or subconscious, leaving a meager 5% busy trying to explain why we act or feel certain ways. And we do this not by tapping into our subconscious, but by making inferences based on our behavior. In essence, we make things up.

So if we can't even tell ourselves the truth, why should we expect customers to provide truthful feedback on satisfaction?

If not satisfaction, then what?

What's a company to do? Customers won't tell you how they feel, or if they try, they're lacking—even incapable of—veracity.

If most of your customers say they're satisfied, but you have a serious attrition problem (i.e., too many customers leaving), you're probably paying attention to the wrong numbers. Rather than focusing on satisfaction responses, look to behavior.

Behavior is the ultimate truth test. What you profess and what you do are often opposing notions. For example, when a doctor asks a patient how much alcohol he or she consumes in a week, the doctor typically doubles the patient's answer. Why? Most people drink more than they think, even if they're trying to be truthful. Do you know anyone who says he or she watches only one or two hours of television each week? More importantly, do you believe them?

The rule of thumb: It's not what they say; it's what they do.

The key is behavior. Don't start with satisfaction metrics, start with attrition metrics. How many customers are leaving and which customers are leaving? After all, your ultimate goal is to keep (and acquire more) profitable customers.