Usability plays a significant role in our lives. Everyday tasks such as driving a car, watching TV or filling out a form involves usability in some way. As technology becomes more complex and diverse, there is a greater need to ensure that users are able to operate it.
Human computer interaction principles have existed for decades for the design of traditional software applications. However, there are several significant differences between traditional software interfaces and designing for the web. Web designers do not have the luxury of knowing where the user will be when surfing the Internet. They may be sitting at home on a desktop computer, travelling on a train or sitting in an crowded cafe.
With a traditional graphical user interface (GUI), developers can control everything that is displayed on the screen. They know which systems they are being designed for, which fonts are installed and in some cases, the screen size. This is not so with web interfaces. Web pages may contain the information in their code, but it is the browser that presents it. Some of the differences between GUI’s and web interfaces are as follows:
- Compatibility – There is a need to design for browser and device compatibility. What looks appealing on a desktop PC browser may not look or act the same on a different browser or on a mobile device.
- Security – The Internet is less secure. Any personal information divulged is at risk of being communicated over the Internet to unwanted parties. Websites have to earn the trust of the users.
- No manual – Unlike many software packages, there is no manual for the Internet. In most cases, users have to be able to be able to use website interfaces intuitively.
- Range of users – With over one and a half billion Internet users in the world (www.internetworldstats.com), the range of user types is diverse. Websites may have to cater for people of different age groups, cultures and capabilities. Accessibility is often a legal requirement for website design.
With over 230 millions websites on the Internet, users have more choices than ever (www.netcraft.com). Website designers are constantly trying to find ways to make websites more appealing for users. If a web page is confusing or difficult to use, they are more likely to leave. If the text is hard to read or the site content does not satisfy their needs, they will simply go elsewhere (Nielsen, 2000). There are many reasons why a user would want to leave a site and after all, it is as easy as clicking a mouse button. Improving the usability of a website can accomplish the following:
- Increased usefulness – the more you cater for the needs of the user, the more likely they are to want to use it.
- Increased efficiency – ensuring that the user can do what they want, as quickly and with as much ease as possible without error.
- Improved productivity – because the site is more efficient and has less errors, the user can accomplish more.
- Improved acceptance – user satisfaction means that users will trust the site and want to return. The better the impression you make on users, the more you enhance the perception of the business or organisation and improve its reputation, which can lead to more visitors.
In his book, User-Centred Web Design, John Cato (2001) explains what he calls the ‘creation trap’. This can be described as the mindset in which developers know what they want from the offset and just want to move on to its creation. Developers often feel the pressure of time, budget and management and want to get something visible done so that they can show progress, with the disillusion that the discovery and design stages are unproductive. In this rush to the creation stage, they begin development too early and suffer the consequences later, when it is often too late.
Many website development managers see the usability studies as an added cost, however, companies who invest their money into conducting usability studies have seen the benefits. A recent study has shown that for websites that have been redesigned for increased usability with 10% of the development budget had an average improvement in key performance indicators of 85% (Nielsen, 2008, Retrieved June 23rd).
The cost of development can be reduced when designing with usability in mind. Often, the first 10% of the design process can establish a basis for 90% of the total cost. Therefore, a usability approach is important to ensure that the site adheres to its goals (Reinersten, 1991).
In summary, the money that is spent on usability is saved in later development when fewer changes have to be made. This creates a significant return on the investment.
“The rule of thumb in many usability-aware organisations is that the cost-benefit ratio for usability is $1:$10-$100. Once a system is in development, correcting a problem costs 10 times is much as fixing the same problem in design. If the system has been released, it costs 100 times as much relative to fixing in design” (Gilb, 1988, chapter 2).