What is usability and why should I care?

This article gives an introduction to usability and explains how it can be applied to improve your product or service, and benefit your business. Let’s start with a definition adapted from Jakob Nielsen:

Usability measures how easy user interfaces are to use.
It also refers to methods for improving ease-of-use during the design process.

User interface is the means by which people interact with a digital product or service such as a mobile phone or a website. Usability, in short, is about measuring ease-of-use and improving it.

The two sides of usability

In Roman mythology Janus, the god of gates and doors, has two faces: one looking to the past and one to the future.

Janus statue in Vatican

Just like Janus, usability has two sides to it. The services offered by usability companies can be divided roughly into two categories:

  1. Review and test the usability of your existing product and provide recommendations on how to improve it (i.e. usability evaluation)
  2. Create a new product to meet particular users’ needs by involving them throughout the design and development process (i.e. user-centred design)

In this simplified view, one aspect of usability is evaluating an existing service from the users’ point of view (“looking to the past”) with a view on improving it, and the other is creating a completely new service (“looking to the future”).

Usability is more than just websites

Badly labelled light switches

Usability is not just about websites; it applies to all man-made products and systems. Usability measures how well users can learn and use a product to achieve their goals, and how satisfied they are with it.

Usability is also not just a step in a process or a methodology but rather a mindset. If you have your users’ best interests at heart throughout your business, you are already practicing usability.

Usability is about focusing on the users’ best interests.

User experience is emotional as well as rational

Usability has traditionally focused on the ‘rational’ aspects of the user experience, like task completion and efficiency. Just as important, if not more, is the ‘feeling’ that your users get from using your product or service and the experience they have with your brand.

The ultimate measure of usability is the sum of the subjective opinions your users have about your product or service. Just like in the real world, a single bad experience can outweigh a number of other factors like price, quality, and availability: “The product was great but the salesman was a tool, and I’m never shopping there again!”

When designing your digital product or service you should always consider the overall user experience, not just the individual ‘features’ or other aspects of the product in isolation.

Why should you care?

You’re focused on making the best product or service in your industry. You want to make sure your customers think of you before the competition.

When your users’ needs, interests, and preferences are considered first, they are more likely to access your website than the competition’s, and subsequently buy your product or service. Specifically online, a usable website allows your audience to:

  • Find your product or service online
  • Once on your website, find the information they’re looking for, such as product details and store locations
  • Understand the information you provide and build trust and confidence in your business
  • Take action and complete tasks, such as making a purchase
  • Have an enjoyable overall experience

Your website users are your potential customers, and they are all real people. If people can’t find your product or service online, they won’t buy it. If people don’t find your website helpful and trustworthy, they won’t use it. If people have a frustrating experience, they won’t come back. If your website doesn’t make people smile, they won’t tell others about it. If people can’t fill in the form or complete the transaction, there is no sale.

By applying usability and user-centric design you can address the above and create websites that your users need and enjoy using.

Flower stall in Italy


Big thanks to Chris, Ben and Gerard for reviewing drafts of this post!

If you have any questions or have a different view on usability please feel free to leave a comment below.

Author: Jussi

Jussi Pasanen is the founder and principal at Volkside