UX Glossary · K
Kano model
A way of classifying features by how their presence or absence affects satisfaction.
The Kano model, developed by Noriaki Kano in the 1980s, classifies product attributes by the relationship between how well they are implemented and how satisfied users are. The categories most used:
- Basic (must-be): expected, and only noticed when missing. Their presence earns nothing; their absence is disqualifying.
- Performance (one-dimensional): more is better, roughly linearly. Speed, storage, price.
- Delight (attractive): unexpected, and their absence costs nothing because nobody was looking for them.
Two further categories, indifferent and reverse, cover attributes nobody cares about and attributes some users actively dislike.
The useful insight
Basic attributes cannot make a product good, only acceptable. Investing heavily in them past the threshold returns nothing, and neglecting them cannot be compensated for elsewhere. Reliable login is a basic attribute; no amount of delight offsets its absence.
The category shifts over time
Today’s delight becomes tomorrow’s expectation. Undo in a web application was remarkable once and is now a basic attribute whose absence reads as broken.
In practice
The classification is most valuable as a prioritisation argument. It explains why a feature users rated highly in a survey produced no measurable satisfaction: it was already expected, and meeting an expectation is invisible.