There is no such thing as an "average user." No human is an "edge case." Many orgs persist in thinking of human behavior as a "process" they can capture and encode in their app. Instead, learn how to clearly define audience segments by their philosophic approach to their purpose. Allow for humanity, see the patterns rather than the demographic assumptions, and then support the patterns.
Better yet, measure how well you support different thinking styles differently--measure how well people can make progress on their purpose.
More details at indiyoung.com/course-thinking-styles/