What is Web Usability?
One of the most important concepts to be considered in web design is usability. "Usability", according to Nielsen (2000), "rules the web". Given this, it now seems ironic that Booth (1989) wrote: "some researchers have argued that the concept is so vague and ambiguous that it ought to be abandoned". Dumas & Redish (1999) defined usability in the context of four basic assumptions. These stated:
- "Usability means focusing on users.
- People use products to be productive.
- Users are busy people trying to accomplish tasks.
- Users decide when a product is easy to use."
Moreover, "Usability is an attribute of the entire package that makes up a product - The hardware, software, menus, icons, messages, manual, quick reference, online help and training." Its official definition according to the ISO is: "The effectiveness, efficiency, and satisfaction with which specified users achieve specified goals in particular environments." This is a rather general definition, which refers to the user experience in all environments. Nielsen (2000) highlights the importance of usability in the electronic environment that is the Internet. Taking a stance from a commercial point of view, he points out how, "usability has assumed a much greater importance in the Internet economy than it has in the past", due to the fact that the web has become "the ultimate customer-empowering environment". His definition (1993) associates usability with five attributes.
- Learnability. The system should be as simple to learn as possible.
- Efficiency. The system should be as efficient as possible to increase productivity.
- Memorability. The system should be easy to remember for future use.
- Errors. The system should have as few errors as possible to ease use.
- Satisfaction. The user should feel a high level of satisfaction when using the system.
Nielsen was able to conclude: "On the Web, if a site is difficult to use, most people will leave." (2002).
The potential for sales growth envisioned by companies worldwide throughout the late 90s saw an explosion in the number of businesses going online. Currently, it is estimated that the worldwide Internet population is 445.9 million (eMarketer)/553 million (Computer Industry Almanac). The projections for 2004 by these two organisations are 709.1 million/945 million respectively .
Possessing a website became a symbol of corporate professionalism. New dotcom companies sprung up literally overnight, fuelling the e-commerce revolution. It seemed anyone who was anyone wanted to have a website. The result was a web awash with companies all vying for our attention. This rush of unprecedented competition empowered the consumer with more choice than ever before. As Nielsen points out, "he or she who clicks the mouse gets to decide everything. It's so easy to go elsewhere; all the competitors in the world are but a mouseclick away." (2001).
What the web has done is reverse the process of traditional usability. "Now users experience the usability of a site before they have committed to using it and before they have spent any money on potential purchases." "In product design and software design, customers pay first and experience usability later. On the Web, users experience usability first and pay later. Very clear why usability is more important for web design." (Nielsen, 2001.)
Usability expert, Vanessa Donnelly was "amazed at how unusable many Web sites were; they seemed to be breaking every single rule that we had painfully learned from the software development process." (Donnelly, 2000 as cited in Web Reference.) All too often websites receive scathing reviews because they have been designed around an internal corporate structure that is completely alien to the outside user. Making user interests and needs a priority is the key to success.
Universal access as well as being an important economic and policy issue is also a fundamental design issue. Designers must accommodate small and large displays, monochrome and colour, slow and fast transmissions. Providing text-only versions for users with small displays and low bandwidth access is likely to be strongly recommended for many years to come (Shneiderman, 1997).
Though usability may initially seem trivial, "on an intranet, if employees perform their tasks more slowly due to difficult design, the company bears the cost of the reduced productivity." Nielsen (2002) estimated that, "low intranet usability costs the world economy $100 billion per year in lost employee productivity".