Do Customers Know Too Much About NPS?

Spring 2023

Net Promoter Score (NPS) is, by anyone’s reckoning, an enormously successful idea. It’s probably the most common metric in customer surveys across the world, and an acronym that pops up regularly in board discussions.

Over the years many people have criticised NPS on various technical grounds, some legitimate and some more a case of trying to promote alternative (often proprietary) measures. But one criticism we haven’t often seen is that the very success of NPS may come to pollute its reliability as a measure of how customers feel, and of their likely future behaviour.

Is NPS too successful?

The premise on which NPS is based is that the score someone gives for their intention to recommend on a 0-10 scale is predictive of their future behaviour, and that there are significant step changes in behaviour between 7 and 8 and between 9 and 10.

The choice of question and cutpoints were originally based on empirical research, but we’d always recommend doing the work with your own customer data to make sure that they are the best choices for you too.

So what’s the problem if NPS is successful? The issue is that as it becomes more and more successful, more and more people will get to know how it works, and that in turn means that there’s a danger the score they give will be affected.

Choosing to give a score of 8 or 9 out of 10 on a scale of 0-10 is very different from choosing whether you want to be a “promoter” or a “passive”. Knowing how NPS works is likely to affect the link between your NPS score and your future behaviour.

We’ve been tracking this on our panel for a few years now. Overall 17% of people have heard of NPS, and 9% of all customers say that knowing how it works affects the score they give. That’s worrying enough, but it gets worse…

Knowing how NPS works is likely to affect the link between your NPS score and your future behaviour.

Who is most affected?


Among younger customers, probably because many of them have worked in organisations in which NPS is used prominently in voice of the customer feedback, there is much greater knowledge of NPS. As the chart below shows, while knowledge of NPS is negligible in older customers, around 1 in 5 customers below 35 says that knowing how NPS works affects the scores they give.

It’s too early to declare a crisis, but we do believe that this is an important trend to monitor. If 1 in 10 of your customers, or even 1 in 5 if your target demographic is younger, is giving a score that is no longer a pure reflection of their attitudes towards you, then that has to bring into question the validity of the conclusions you are drawing from your survey.

Stephen Hampshire

Client Manager
TLF Research