Usability testing is one of the qualitative methods that allow us to observe and understand user behavior patterns. During usability tests, we observe users interacting with products, identifying issues with usage, navigation, information comprehension, and questions that arise during interaction with the product and interface.

We can also observe behavior patterns that help us understand and categorize different interaction styles and problems encountered.

Therefore, usability tests, along with user interviews, are the foundation of user-centered design. They allow us to design a product based on user experience, uncover hidden problems, and reduce future costs.

Additionally, usability tests are an indispensable complement to quantitative analysis techniques such as web analytics: while web analytics show aggregated behaviors, usability tests help us understand the reasons behind those behaviors.

The result of usability tests provides metrics of usability: effectiveness, efficiency, and satisfaction.