Usability testing: why is it necessary?

What is usability testing? Why is it necessary? What are the goals? Who are we “testing”? These were my questions when I started my journey into the field of UX design. Today we will talk about my observations and insights into this UX research methodology, including what makes a successful usability test.

First and foremost, a usability test is not exactly a test. We are looking for flaws in our design, not our users, so avoid using the somewhat interchangeable term “user testing.”

What is usability testing?

A facilitator, (sometimes you, as the designer) asks 5 different participants to perform a list of tasks using the product that has just been designed. While the participant completes each task, the facilitator observes the participant’s behavior and gathers feedback for further iteration. (Nielsen Norman)

Why is it necessary?

We may think that we have created a useful product that is easy to navigate and brings delight to our audience, but how would we know that without testing it with real users? No UX designer is capable of designing an exceptional user experience without iteration based on the feedback of users.

What are the goals?

There are a few common goals for most, if not all, usability tests.

  1. Find problems with the current design. What are users getting stuck on? Are they confused about anything? Are certain tasks taking longer than others? Encourage users to think aloud and observe their body language while they complete the tasks you have given them.
  2. Discover opportunities to improve the design. How can we iterate on what we have to improve usability?
  3. Learn more about our users. How are they behaving? What do they like? What do they dislike?

Who are the participants?

All of the participants should be people who would realistically use your product. In cases where the product already exists, they could be current users. If the product does not yet exist, the participants could match your persona/target audience, or have a need for or interest in the service that your product would provide them.


Now that we have gone over what a usability test is, let’s talk about how to facilitate one. The facilitator asks questions and guides the participant through the interview. As the facilitator, you will give instructions, guide participants through the list of tasks, answer any questions they might have, and ask questions that do not influence them. If the questions influence the participant, you won’t get valid data. I find that people subconsciously want to agree, so if you ask a biased question like “What was confusing about this task?” they will come up with an answer, even if they didn’t find the task particularly confusing. Instead, ask questions like “Can you show me and tell me how you would get through this task?” Then, have them rate how easy or difficult it was to get through. Make sure you are encouraging your participant to think out loud, even when they are not directly answering one of your questions.

Examples of tasks

For these examples, I will be using a project I recently worked on. It was a mobile website aimed at helping people quit smoking by joining social groups. We were testing the MVP with users before moving forward with all of the features.

Task 1- Show me and tell me how you would go about joining the yoga community.

Task 2- Show me how you would join a current live stream event.

Task 3- Show me how you would go about getting more information about each of these groups.

Types of data

You can collect both qualitative and quantitative data from usability tests. Qualitative usability testing focuses on collecting insights, findings, and anecdotes about how people use the product or service. Qualitative usability testing is best for discovering problems in the user experience. This form of usability testing is more common than quantitative usability testing. Quantitative usability testing focuses on collecting metrics that describe the user experience. Two of the metrics most commonly collected in quantitative usability testing are task success and time on task. (Nielsen Norman) I personally like to collect both types of data, because the metrics from the quantitative results can help us figure out what our top priorities are when iterating.

In conclusion

This might seem obvious, but make sure you are recording your usability testing sessions, as well as taking notes. Pay attention to your participant’s body language and other subconscious cues. These can tell us a lot about the experience they are having while using your product.

Don’t ask leading questions, they will end up influencing the answers of your participant.

Make sure the participant feels comfortable. Generally, people don’t want to talk when they don’t feel comfortable. Some small talk before the interview is usually appreciated. If you’re in person, offer them some water. Overall, just make sure that they feel ok about opening up to you.

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