The answer is 5, except when it's not. Most arguments for using more test participants are wrong, but some tests should be bigger and some smaller.| Nielsen Norman Group
User interviews help you learn who your users are, what their experiences are like, and what they need, value, and desire.| Nielsen Norman Group
Unlock the full potential of UX research and turn users into the decision-makers. Discover methods and strategies to elevate your product, boost adoption rates, and drive informed decision-making.| Maze
Cognitive bias of failing to disregard information only available to oneself| en.wikipedia.org