usability is not a goal

Usability is Not a Goal

It’s a result.

HCI Graduate Student OrganizationIowa State University

November 2, 2005Steven Pautz

““Usability is Not a Goal

Usability is not a goal: it’s a result.

A desirable outcome.

Usability by itself isn’t enough—we need a balance of many different things:

Usability, Usefulness, Aesthetics, etc.

The way to this balance is good design,which requires a good design process.

““Usability is Not a Goal » Overview

““What Usability Is

Usability is an attribute;a measure of quality.

There are many definitions of usability,and many associated attributes:

Effectiveness Efficiency Satisfaction Desirability /

Likability User Frustration

““Usability is Not a Goal » About Usability

Intuitiveness /Intuitability

Learnability Memorability

and many more...

““Knowing Isn’t Enough

Simply knowing about usability isn’t much use, though:

We need to create usable systems.

This is easier said than done, though...


““What Usability Is Not

Usability is a necessity, but it’s not a magic cure-all. There are many other important and desirable traits:

Functionality Stability Performance Aesthetics

If we only focus on one specific trait,the others will suffer.


Accessibility Development Cost Marketability and so on...

““What Should We Aim For?

These traits are all interrelated:

Changes in one will affect the others.

Aiming for usability alone is reckless;we must somehow aim for everything.

““Usability is Not a Goal » The Goal

““What Should We Aim For?

These traits are all interrelated:

Changes in one will affect the others.

Aiming for usability alone is reckless;we must somehow aim for everything.

Rather than aim for a desirable trait, we should aim for a process which will yield many desirable traits.


““Aim for a Design Process

“Where do you spend time: Getting the“design right, or getting the right design?”

~Bill Buxton

By formulating the right design early on,we can avoid surprises at the end.

Design processes ensure that:

We come up with the right design

That design actually gets created


““A Review Thus Far

There are many desirable attributes;usability is important, but it’s not alone.

We want to create systems which get high marks in all desirable attributes.

Aiming for attributes doesn’t help us,though, as they’re only outcomes.

So, instead of aiming for an outcome,we aim for a design process which will yield those outcomes.

Next up: Anatomy of a design process.


““Design Processes at a Glance

Good, balanced design is not easy.

A good design process is a structured methodology, a plan of attack.

It ensures we address—and achieve—all of the desired results.

It helps us avoid opinion, speculation,and other “common sense” pitfalls.

““Usability is Not a Goal » Design Process Overview

““Structured Methodology”

“Structured” doesn’t necessarily mean rigid or formal—it just means we don’t wander aimlessly.

There are dozens of different approaches and methodologies for design, all with different requirements and strengths.

The purpose is always the same:ensure the final result comes out right.


““Common Pitfalls

Speculation—even informed speculation—can lead to poor decisions.

Opinions can blind us to the true cause behind success or failure, or prevent us from recognizing success/failure at all.

Mismatched mindsets, such as applying an engineering mentality to a design problem, fail to solve the problem.

These can be minimized with a data-driven design process.


““An Sample Design Process

1 Get to know your users. Determine their needs, goals, and desires.

2 Brainstorm several high-level designs to meet those needs, goals, and desires.

3 Evaluate the competing designs,and select the best one.

4 Implement the design. Test along the way. Add low-level details as needed.

5 Evaluate the final implementation.Ensure we built what we aimed to build.

““Usability is Not a Goal » Sample Design Process

““A Good Start…

That process is far from ideal,but it’s quick and easy.

A few good practices:

Talk directly to users; don’t guess or speculate about what they might want.

Focus on “high-level” design first.

Consider several alternative designs.

Test, test, test. Then test some more.


““…But Room for Improvement

That process is quick and easy,but it’s far from ideal.

A few dangers:

Opinion and speculation can still interfere with the process.

This may yield decent usability, but it neglects several other factors.

The designer must ensure that appropriate HCI and design techniques are used.


““High-Level Design”

HCI and design are about interaction,not interfaces.

Interaction is about activities and user experience.

We should design the higher-level activities and experience first,

then design the interaction,

then design the interface.

““Usability is Not a Goal » The Purpose of Design

““Usability is Not a Goal

Usability is not a goal: it’s a result.

A desirable outcome.

Usability by itself isn’t enough—we need a balance of many different things:

Usability, Usefulness, Aesthetics, etc.

The way to this balance is good design,which requires a good design process.

““Usability is Not a Goal » Overview

usability is not a goal

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