When building a scenario, it sets a scene for a user in their day to day activities discovering interaction for the designer’s interface. When creating a scenario, you must ask yourself who what where when and how a person may use this interface.
Creating personas also help identify any faults in the design, when something may not be realistic there is often a problem that needs to be fixed in the design itself. Setting examples of how a user may perform a task is a great way to identify a problem allowing the interactive to satisfy the users desired outcome.
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