Quality attributes: Usability

«Ouch, that website is terrible! Better find an alternative»

Sounds familiar?

A software system, like a website, should work -of course!- and should be easy to use.

That’s why, when eliciting requirements, you should also focus on Usability.

So… what is Usability?

Usability describes how easy it is for users to perform required tasks.

The more the system is usable, the better the user satisfaction.

If the system is easy to use, users will perceive a better overall quality of the system.

If users are satisfied, they

• Won’t leave your system (unsubscribe/uninstall)
• Spread the word and let you acquire new customers.

So, yes, usability is a fundamental aspect of any system and should be taken into account.

Users should be able to learn how to use your software. So, you should also pay attention to LEARNABILITY.

If the software is intuitive, users won’t spend too much time trying to make it work.

So, learnability impacts usability (and user satisfaction)

ISO/IEC 25010 defines Learnability as

the degree to which a product or system can be used by specified users to achieve specified goals of learning to use the product or system with effectiveness, efficiency, freedom from risk and satisfaction in a specified context of use.

How to improve usability

Now, let’s see some ways to improve usability:

🔸 accessibility 🔸 useful feedback 🔸 nice visual design

Accessibility

the system must be easy to use also for people with disabilities.

👉 Alt text to images 👉 logical order and grouping for form fields 👉 system usable when using only the keyboard

and more

Useful feedback

The user should easily understand the system, with hints like

👉 tooltips 👉 meaningful error messages

Nice visual design

A clean, elegant website (or application) is easier to understand and use.

👉 use an easy-to-read font 👉 use simple navigation and menus 👉 use consistent colors, themes, icons

How to measure Usability?

You can measure

⌛ the time to complete a task ❌ error rate 🌟 customer satisfaction, using forms or interviews

Read more here👇 https://www.nngroup.com/articles/usability-metrics/

Wrapping up

Usability is a software attribute that, even if not strictly technical, is crucial for the success of our applications.

It’s quite simple to improve and makes a huge impact on the user experience.