Assumptions vs Usability Testing

[Janet Valade <janetv -at- systech -dot- com>]

In light of our recent discussion of the need for usability testing, I
thought I would tell you about a phone call I just received. I think it
illustrates totally the need for usability testing (not that I ever get to
do any).

The phone call was related to my on-line manuals. I have all our product
manuals on-line in HTML format for users. The front page is a TOC. There is
a search engine interface on the TOC page. There is also a button link to
the Index for the Manual. I put the Index button at the top of the TOC so
that it would be very visible, so users would know there was an index. I
thought this was all quite clear and easy for users. E.g.,
http://www.systech.com/support/rcs4kagg/rcs4ktoc.htm

I just got a phone call from one of our staff who was looking for
information to interpret LED patterns on one of our products using the
on-line manual. He said he looked in the Index and couldn't find an entry. I
was sure there was an entry in the index. I clearly remembered putting in
several. So, I went to the index and, sure enough, under L were several
entries for LED. Also, when I put LED into the search field, I get several
hits.

Further conversation was pretty enlightening for me. The person who called
me, a perfectly intelligent person, simply had a different perspective and
*saw* the page differently than I see it. He saw the "index button" as a
heading, rather than a link, and thought the entries were under a heading
called Index. Thus, the statement that he looked through the Index and
didn't see anything about LEDs. He was actually looking through the TOC.  I
can, *now*, see how that could be an interpretation and that I need to fix
this. The cause of the problem is my mindset, with its assumptions. Because
I know so clearly that a TOC and an Index are totally different animals,
like a house and a car, it never occurred to me that someone could look at a
TOC and think it was an Index. Or that anyone would not know that if you
were in a TOC, you would have to go somewhere else to be in an Index.

The other problem is that he just didn't see the search field. I couldn't
possibly have this problem because I knew it was there. I put it there. So I
also need to fix this problem. 

The point being that neither of these problems would ever have been
identified by me, no matter how many times I looked at that page. It was all
clear to me. A new viewpoint, with a different perspective, was needed to
reveal the problems.

Janet

Janet Valade
Technical Writer
Systech Corporation, San Diego, CA
mailto:janetv -at- systech -dot- com