Usability Testing Metrics and How to Use Them

"Usability testing should always be part of product development. Ideally, it is conducted before release, but in practice it can be useful at different stages. It's worth pointing out that, "testing" isn't a goal in itself. Without knowing exactly what you want to measure, you risk ending up with feedback you can't interpret or act on. Every usability study can focus on a different aspect of the experience, and the right metrics depend on your research goals."

"Suppose your team has just released a new "Add to Wishlist" feature in an e-commerce app. You want to understand whether users can find and use it without confusion. For this, you recruit 5 participants and give them realistic tasks, such as "Find a product you like and add it to your wishlist." As we go through the metrics, we'll refer back to this example to see how each measurement works in practice."

Usability testing should be integrated into product development and can be valuable at multiple stages. Testing must target specific measures so feedback remains interpretable and actionable. Different studies focus on distinct experience aspects, so metric selection depends on research goals. A practical scenario: a new 'Add to Wishlist' feature is tested with five participants given realistic tasks like 'Find a product you like and add it to your wishlist.' Task success rate is a primary binary metric, often benchmarked (commonly 80%) to decide readiness. Time on task measures how long completion takes and complements success rate by revealing efficiency differences.

Read at Medium