Web Usability Blog

What is the purpose of usability testing

Written by Dr Sarah Burton Taylor | Dec 10, 2021 11:18:37 AM

Usability testing is the best way to find out if your site is effective – that is, will it work with real users and help you achieve your online goals. Watching real users interacting with a site or app (both in development and live) is the best way to understand the issues that interfere with a good user experience; it also forces those with responsibility for the site or app to ‘walk in the users’ shoes’ – often an unsettling experience!

What is usability testing?

Usability testing is the process of testing how easy or difficult a website is to use with a representative group of users and surfaces why problems are happening. It is qualitative research that focuses on behaviours not attitudes – because what people say they do is often different to what they actually do.

Representative users undertake realistic tasks on a site, whilst a UX researcher watches what they actually do. By getting them to think out loud about what they’re thinking or feeling, and observing their body language and facial expression you can identify the ease of use and intuitiveness of the interface.

Why is usability testing important?

  • ‘Real’ users are different to the people who work on the site: they don’t understand the background of the site; they don’t know how it is structured; they don’t know what content and functionality has been included. Additionally, they often have poor or average skills in using desktop or mobile functionality. Consequently, they can behave in completely unexpected ways.
  • User feedback at any stage – prototype or live site - will result in an improved user experience, both from a usability and content point of view. This will improve user satisfaction on all sites and conversion rates on transactional sites
  • Seeing ‘real’ users interacting with a site (be it prototype or live) challenges existing mental models about how the world works and, therefore, the assumptions underpinning design choices
  • Usability testing also challenges subjective decision making, instead of sitting around and debating the merits of various solutions within the team, it allows the user to make the decision by their behaviours demonstrating which is the most effective route
  • Usability testing will get feedback on a ‘macrostrategic scale – do users understand the concept on your website or app?
  • And feedback on a more ‘micro’ tactical scale – focusing on specific elements of the interface
  • Usability testing may also surface issues outside the user interface e.g. issues about organisation branding and credibility, other offline requirements, that will enable the overall online and offline user experience to be improved
  • Usability testing will enable prioritisation, surfacing what’s most important to users and identifying where development effort should be concentrated
  • Usability testing helps to pull together the client and the developer team to help ensure that their understanding of the user goals are aligned, and that they have a clearer joint picture of what ‘success’ of the site will be.

How to do usability testing

We always recommend usability testing early and iteratively in the web development process to save you time and money. It will also result in a better outcome as your site will have been developed with users at the centre of it. (Read more what are the benefits of testing early).

No matter the stage you begin testing, there are two main approaches:

  • Moderated – users undertake tasks using think aloud protocols in moderated research with a facilitator either in a lab or remotely using desktop sharing software
  • Unmoderated - remote testers (usually from a panel) are given a task and asked to ‘think out loud’ whilst using a site. Their session is recorded ready for subsequent analysis

Unmoderated research is usually cheaper; however, it requires questions to be pre-defined. Often the most insightful questions are prompted by testers’ behaviours during a research session and are not anticipated in advance. It also only tends to be suitable for a limited number of simple easy journeys.

Bespoke moderated usability testing -either in the lab or remotely - enables more complex user journeys to be investigated and more follow-up questions and probes to understand in more detail the issues with the site.

For the majority of our usability testing projects, we like to follow the below process:

  1. Set clear objectives – this will affect the type of people to be recruited to test the site and the structure and content of the facilitation guide
  2. Recruit your testers - while you don’t need large numbers, you do need the right testers, otherwise you will not get meaningful feedback on both the usefulness and the usability of the site
  3. Write a facilitation guide – this will inform your discussion with testers and help to gain buy in to the research process from key team members early on in the process
  4. Undertake the testing – remember to be prepared and don’t be afraid of silence, this is often when you gain the most insightful comments from testers
  5. Analyse the research - pull together the issues at a macro and micro scale help you improve your user experience but also increase your site success
  6. Tell your team – there is no point in doing the research if you don’t then share your results! The more people you can get to buy in to the process, the easier it will be to implement changes