Introducing User-Centered Systems Design - Foundations for Designing User-Centered Systems - page 10

1.3.1 Benefit 1: More Usable Products
Understanding people can help you design systems that are more usable, more
learnable, and more efficient. For example, the adoption of email has become more
widespread because of wider availability of devices and infrastructure but also
because email interfaces have progressed from requiring in-depth computer sci-
ence and systems administration knowledge to manage installation and use to
relatively easy-to-use web interfaces with help documentation, message manage-
ment and retrieval, directly usable features like formatting, and the ability to easily
attach or embed multimedia.
Web design provides another example. Changes in the costs of hardware and
bandwidth have made it faster and cheaper to develop web pages, but many people
and businesses would not be generating as many web pages if they still had to use
raw HTML. The rise of special purpose, easy-to-use HTML editors (e.g., Webbly)
is one reason for the massive uptake of the web (Holmes 2005 ). AOL and the
initial Netscape browser were both successful products because they made an
existing service more usable and more widely accessible. Work in eCommerce
suggests that ease of use of existing products and the expected cost of learning to
use a new interface can also lead to a type of brand recognition and later to loyalty
(Johnson et al. 2003 ).
Sometimes the usability of a tool does not increase directly through improving
an interface but because its utility increases and its frequency of use increases. The
decreasing weight (and size) of cell phones has made them easier to carry around,
and thus always available. Part of the success of the web arises out of the creation
of search engines: Bing, Google, DuckDuckGo, Ask, and the more specific search
engines like Citeseer and DBLP (dblp.uni-trier.de) increase the usability of the
web by helping users find information based on the topic they are looking for
rather than by the location of the information. This increase of usability is not
driven by the visual interface, but at a deeper level of supporting the user's tasks.
Users sometimes have problems in understanding what they are looking at.
Norman ( 2013 ) refers to this as the Gulf of Evaluation. Users also encounter
problems in knowing or being able to discover what they have to do to execute
their task using a particular interface. Norman describes this as the Gulf of Exe-
cution. The Internet examples above are examples where the Gulf of Execution has
been made smaller, and thus made more tractable for a wider range of users. We
will return to Norman's Gulfs in Chap. 12 .
More often, lack of understanding of users leads to some groups of users being
excluded. We have worked with web sites that now make sure that they have text
versions available to support not only the visually impaired (through text readers
and descriptions of pictures), but also two types of users that do not come to mind
easily in a US college environment with ubiquitous broadband—those users sep-
arated from the site via dialup lines or by vast distances (Ritter et al. 2005 ).