Interviewing users on a regular basis is not just important. It is essential for understanding consumer behaviour and enhancing behavioural design.

During my masterclasses on user interviews, someone always asks, "How many people should I interview? Is there a formula?" This was also my question at the beginning of my career until I decided to create a formula myself.

Introducing NOREX.

The NOREX framework is designed to refine participant selection beyond traditional demographic methods, such as age or gender, by focusing on user engagement frequency. It offers a strategic method to understand diverse user experiences by categorising users into five distinct groups.

Firstly, we have 'N' for Never: these are potential users who have never interacted with your product. Next are 'O' for Occasional Users: those who interact with your product sporadically, without a consistent pattern. Understanding their triggers or barriers could provide insights into sporadic engagement. Then, 'R' for Regular Users: this group uses your product consistently. 'E' stands for Extreme Users: these users engage with your product more intensely than typical customers. Finally, 'X' for Ex-Users: former users who have stopped using your product. Understanding why they left can uncover critical insights into product limitations and user dissatisfaction.

After sharing this formula, I always recommend conducting at least five interviews per week. This practice enhances your understanding of your user base and uncovers how things could improve for them. Remember, there is always room for improvement.

Using the NOREX framework can provide invaluable insights into consumer behaviour, helping you to fine-tune your product and marketing strategies. By categorising users based on their engagement levels, you gain a more nuanced understanding of their needs and experiences. This allows for more targeted and effective interventions, ultimately leading to better user satisfaction and loyalty.

If you decide to use NOREX, let me know how it works for you and if you uncover anything new. Your feedback is invaluable as we strive to continuously improve our approach to understanding and meeting user needs.