In today’s competitive world, innovation is a top priority for companies. That’s why understanding customers' needs is crucial for developing the right products or services. However, identifying these needs can be difficult as they change rapidly (von Hippel, 2001).

To address this challenge, various methods have been developed to help companies involve users in product development. For instance, the lead user method which recognizes users' ability to provide valuable insights for both needs and solutions. Nevertheless, implementing this method can be hard, as it requires identifying specific user types. For that reason, it is essential for companies to understand the different methods available to choose the most suitable one for their needs.