Usability is one of the user experience design disciplines. Other disciplines include visual design, information architecture, and interaction design.
Ignore it, and good luck having users “use” your product, whether that is a website, a mobile app, a system, or a device.
What is usability?
In simple words, usability is how easy it is to use an interactive device, system, or website.
When you decide to design a product, you are trying to solve your customer’s problem. You want to provide your customer with a functional product that is easy to use, and therefore useful.
Why usability testing is important?
Designers are usually attached to their designs, and so usability testing is conducted with a set of real users, who are the target segment for that product to provide feedback.
Usability testing is conducted to measure the usability of that product to those real users.
What to test? What are we trying to measure in usability?
Whitney Quesenbery (2003) outlined five usability dimensions to help measure the level of usability of a certain design, and have I added a sixth one, “memorability”.
- Learnability: How easy it is to learn your way around the new system? Did the user require external help? Did he have to look through a manual?
- Efficiency: How long did it take you to perform a task? Seconds? Minutes? Hours? The whole day trying to figure it out?
- Effective: How easy was it to carry out the task accurately? Were you able to complete the task?
- Error tolerant: How many mistakes did you make while performing the task? Were you able to fix it right away or had to do the whole thing again from the start?
- Engaging and satisfying: Did you enjoy performing the task? Was it a pleasurable experience or did you have to dread doing it?
- Memorability: How easy it is to remember how to perform the task after not doing it for a while?
It is simple.
If it’s not easy to use, no one will use it.
… and before you know it, your customers moved to your competition.
It might be a click away.