The Enormous Benefits of Good Web Design
Imagine the productivity benefits we could gain through proper design. Based on an actual system that requires processing of 4.8 million screens per year, an analysis established that if poor clarity forced screen users to spend one extra second per screen, almost one additional person-year would be required to process all screens. Twenty extra seconds in screen usage time adds an additional 14 person years.
The benefits of a well-designed screen have also been under experimental scrutiny for many years. One researcher, for example, attempted to improve screen clarity and readability by making screens less crowded. Separate items, which had been combined on the same display line to conserve space, were placed on separate lines instead. The result: Screen users were about 20 percent more productive with the less crowded version!
Other researchers reformatted a series of screens following many of the same concepts to be described in this book. The result: Screen users of the modified screens completed transactions in 25 percent less time and with 25 percent fewer errors than those who used the original screens. Another researcher has reported that reformatting inquiry screens following good design principles reduced decision-making time by about 40 percent, resulting in a savings of 79 person-years in the affected system.
In a second study comparing 500 screens, it was found that the time to extract information from displays of airline or lodging information was 128 percent faster for the best format than for the worst. Other studies have also shown that the proper formatting of information on screens does have a significant positive effect on performance.
Cope and Uliano (1995) found that one graphical window redesigned to be more effective would save a company about $ 20,000 during its first year of use. In recent years the productivity benefits of well-designed Web pages have also been scrutinized. Baca and Cassidy (1999) redesigned an organization's homepage because users were complaining they were unable to find information they needed.
These designers established a usability objective specifying that after redesign users should be able to locate the desired information 80 percent of the time. After one redesign, 73 percent of the searches were completed with an average completion time of 113 seconds. Additional redesigns eventually improved the success rate to 84 percent, and reduced the average completion time to 57 seconds. The improvement in search success rate between the first redesign and final redesign was 15 percent; the improvement in search time was about 50 percent. (This study also points out the value of iterative testing and redesign.)
E-Commerce Websites Benefit too from Good Design
Fath and Henneman (1999) evaluated four Web sites commonly used for online shopping. Participants performed shopping tasks at each site. In three of the Web sites about only one-half of the shopping tasks could be completed, and in the fourth, 84 percent were successful. (In the former, one-third of the shopping tasks could not be completed at all!) The more successful, and more usable, site task completion rate was about 65 percent higher than that of the less successful sites. We can only speculate how this might translate into dollars.
Numerous other studies illustrating the productivity benefits of good interface design are sprinkled throughout this text. Additional benefits also accrue from good design (Karat, 1997). Training costs are lowered because training time is reduced, support line costs are lowered because fewer assist calls are necessary, and employee satisfaction is increased because aggravation and frustration are reduced.
Another benefit is, ultimately, that an organization's customers benefit from the improved service they receive. Identifying and resolving problems during the design and development process also has significant economic benefits. Pressman (1992) has shown that for every dollar spent fixing a problem during product design, $ 10 would be spent if the problem was fixed during development, and $ 100 would be spent fixing it after the product's release.
A general rule of thumb: Every dollar invested in system usability returns $ 10 to $ 100 (IBM, 2001). How many screens are used each day in our technological world? How many screens are used each day in your organization? Thousands? Millions? Imagine the possible savings. Of course, proper screen design might also lower the costs of replacing "broken" PCs! (Read our last article here for a reference to this – The Importance of Good Design).