User-friendly: how to know your software is usable

Usability is the new motherhood and apple pie: unquestionably good … and almost as hard to find.

Everyone agrees that software should be user-friendly. But what does that actually mean? I’ve been architecting a LOT of desktop software in the past few months, and I’ve been revisiting some of my ideas about usability.

While it’s true that there are a million different factors involved in creating software that people love to use, the five key measures that Nielsen and Schneiderman created stand out in my mind:

  • Efficiency
  • Learnability
  • Errors
  • Memorability
  • Satisfaction

Efficiency
Can users do what they want to do quickly, simply, and without a lot of fuss? Or do they need to fight your software and perform circus contortionist acts to do what they want to do?

Learnability
Have you designed your software, menus, buttons, and tabs so they are easily understandable, even for a first-time user? Or is a first-time user completely lost and unable to proceed without a manual or a training session?

Errors
This is strongly related to learnability – how many errors do new users make? Do they continually make the same or same kind of errors? If they make an error, how easy is it to reverse, correct, or undo the error?

Satisfaction
How do users feel while they are using your application? After? Is it frustrating? Do their stress levels rise? Does the software give them a feeling of competence and power, or ignorance and failure?

. . .

As mentioned previously, there are a million other factors that influence software usability. And it can be hard to measure – there’s usually not a binary yes/no answer.

But if your software scores high on these five attributes with users, chances are you have strong usability. And, chances are people will like the software well enough to use it, talk about it, and maybe even purchase upgrades for it.