What is the purpose of a System Usability Scale (SUS)?

The System Usability Scale (SUS) is a widely recognized tool specifically designed to assess the usability of products, particularly software. Its primary purpose is to provide a quick and efficient measure of a user's experience with a system, focusing on various dimensions of usability, such as learnability, efficiency, and satisfaction.

Using a 10-item questionnaire, SUS captures users’ subjective evaluations of the system they interacted with, allowing designers and developers to gauge how effectively users can accomplish their tasks and how they feel about the usability of the design overall. The results typically yield a score that reflects the perceived usability, enabling teams to identify areas for improvement and ultimately enhance the user experience.

In contrast, other options do not align with the core intent of SUS. Predicting market trends, assessing user engagement, or evaluating aesthetic appeal involves distinct metrics and methodologies that fall outside the usability focus that SUS emphasizes. Therefore, the understanding and application of the SUS make it an invaluable tool for measuring usability in UX design practices.