[Sigia-l] RE: UCD and Usability Testing (was: Usability testing into the dustbin?)

[Boniface Lau]

> From: sigia-l-admin at asis.org [mailto:sigia-l-admin at asis.org]On
> Behalf Of Mitchell Gass
>  
> At 07:43 PM 5/2/2003 -0400, Boniface Lau wrote:
> >"Usability by design" means usability should be designed-in, not
> >tested-in...A team staffed with people capable of usable design
> >tends to produce systems containing relatively few usability
> >problems before testing...In contrast, a team staffed with people
> >relying on usability testing tends to produce systems filled with
> >usability problems before testing...It is a sloppy way of creating
> >usable systems.
> 
> What I'm reacting to is a blanket rejection of usability testing, 

I do not see a blanket rejection of usability testing in Larry's 
article:

http://www.usabilitynews.com/news/article1058.asp

Instead of 'test early, test often, and test iteratively', one should
focus on 'robust and disciplined design processes' because 'the more
problems lurking in the system to be tested, the more hopeless the
fate of those who put their faith in testing.'

Usability testing is a gauge to a system's overall usability. When you
sample the light bulbs coming out of a production line and find a
larger than expected number of bad light bulbs, you know there is a
problem up stream in the process. So, you reject that batch and try to
correct the up stream problem.

But people forgetting the proper role of testing would suggest doing
as much sampling as possible to the point of testing all light bulbs.
Not a wise way of responding to up stream problems. And yet, we have
people doing similar things in usability by suggesting ongoing
usability testing:

http://www.uie.com/Articles/eight_is_not_enough.htm

Usability is supposed to be designed-in, not tested-in.


[...]
> One way I explain usability testing is with a circus analogy: if
> design is a hire-wire act, usability testing is the safety net. You
> never want to use the safety net. You never try anything unless
> you're confident it will work. But if your judgement about what will
> work isn't perfect, or if you simply make a mistake, the safety net
> gives you another chance.

Seeing usability testing as giving a second chance means testing all
light bulbs coming out of a production line.


> 
> Designers who never do anything daring may not need a safety net. 

And there are successful daring wire-walker not using safety net. It
depends on how much one masters the skill with confidence.


> If your designs are all small variations on previous solutions in
> well-understood domains, it's like walking a wire two feet off the
> ground. But when anything about a design is fundamentally new,
> there's risk. Usability testing is a way to minimize that risk and
> support innovation.

Usability testing provides information for assessing risk.

For usability testing to minimize/eliminate risk, you need to test all
things with all users. It is like testing all light bulbs.


> 
> My advice to design teams is always to test what they believe will
> work.

Excessive testing is suitable for people not sure of what they are
doing.


Boniface