Net Promoter Score is the Most Overrated Metric in Customer Experience

I think the Net Promoter Score (NPS) is one of the most overrated metrics in customer experience. Anyone who's ever attended one of my lectures probably knows this already.

On paper, NPS looks beautifully simple. You ask: "How likely are you to recommend us to a friend or colleague?" on a scale from 0 to 10. Then you group people into three neat categories: Detractors (0 - 6), Neutrals (7 - 8), and Promoters (9 - 10). Subtract Promoters from Detractors, and voilà - you've got your number. Easy to capture, easy to compare, easy to throw on a dashboard.

But here's the problem: the more I've worked with NPS, the more I've realised it tells you far less about the customer, and far more about the contextual anchors shaping their answer in the moment.

If you ask me how likely I am to recommend my bank just after they've approved my loan, I'll happily give you a 9. Ask me the same question right after I've spent 45 minutes on hold trying to fix a payment error, and you'll be lucky if I say 2. Neither score reflects my long-term loyalty. They reflect the emotional residue of whatever just happened.

And those anchors don't stop there.

In South Africa, for example, we grow up with grading anchors baked into us: 80% is a distinction in Matric, 75% is a First at university, and in many courses a mere 50% will get you through. Over years of schooling, we learn what "good" looks like, and we carry those anchors into how we rate experiences. A "7" for one person might be the equivalent of a "9" for someone else. Yet in NPS-world, the 7 doesn't count at all.

Behavioural science shows we're terrible at separating the overall from the immediate. We anchor to whatever is fresh in our minds: the last interaction, the tone of the conversation, even the weather outside. Those contextual anchors have an outsized influence on how we score, and that's why NPS often tells you more about timing than loyalty. It's like trying to measure someone's health by asking how full they feel after lunch.

The irony is that companies treat these shaky numbers as gospel. They tie bonuses to them. They obsess over small movements up or down. But those movements might just reflect a rough call centre shift or a technology outage on the wrong day, not a real change in customer loyalty.

What we should be measuring are behaviours that reflect trust, ease, and stickiness. Do customers come back? Do they abandon halfway through? Do they feel confident enough to choose the same provider next time? Those are far more telling than whether someone shaded in a 7 or 8 on a colour-coded bar.

NPS is seductive because it feels simple. But it rests on shaky cognitive foundations. If we really want to understand customer experience, we need to stop asking people how they feel in the moment and start observing what they actually do. NPS has its place, but you get the most out of it when combined with behavioural data that shows what customers are really experiencing.

The number on the dashboard isn't the customer experience. It's just an echo of context.