Definition from Matthew Weprin
“A person who lies at the periphery of a group of users. Extremes can can include age, ability, occupation, experience, etc. Rather than designing for a composite or “average” user, a design team will oftentimes look to extreme users for surprising and actionable insights. Focusing on extreme users can lead to more innovative solutions, more profound insights about a group of users. and new, untapped markets for a product or service.”
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