Mistakes in user interactions often come from a disconnect between what users expect from a system and how it's actually designed. If users have a wrong idea about how the system works, they might use it incorrectly. For example, if users try to delete an email but the delete icon looks unusual or unclear, they might end up archiving the email instead. This happens because the interface doesn't clearly show how to perform tasks (gulf of execution) or how the system responds to these actions (gulf of evaluation).

Assuming that users will just learn to understand a complex system is not a good strategy. If a system is too hard to use, people are likely to give up and go somewhere else. That’s why it’s crucial to align the design with what users already know and expect, helping to prevent mistakes and improve overall satisfaction.