I saw these flyers on each table in a local French Subways. They ask customers to use the app-based customer loyalty card and rate Subways:

The rating is obviously based on the NPS but notice how the levels are grouped and represented. The smiley with the heart eyes (raving fan) represents a value of 9 or 10; the weeping smiley represents a 7 or 8 while the angry smiley represents anything below 7.

Essentially the 11-scale NPS rating has been reduced to a 3-scale rating (ecstatic, unhappy and angry) of which two options are obviously negative. I am a fan of an odd number of options with a neutral element and a balanced number of negative and positive options because I believe that caters best to everyone’s opinions. In the Subways example, which option would you choose if you thought the experience was good but not mind-blowing? There is no option for that or what about if you thought: “hmph, I don’t have a strong opinion because it was neither really good nor really bad”?

This type of legend for the rating invalidates the NPS. Users are no longer able to make a very nuanced choice on an 11-point scale; instead they are being forced to select a 9 or a 10 if they did not find the experience negative. An NPS score based on “coerced” data like this is not valid. The data can really only be used for a rudimentary determination of the ratio of positive versus negative customer experiences…