Usability is a term that gets tossed around a lot in today's web culture. Large companies have spent millions of dollars hiring “usability” consultants and doing in depth studies. It is a subject of much discussion and can mean the difference in the success or failure of a web-based application or web site. The difficulty is that there is no one hard and fast rule. What makes a site usable for a particular group may make it totally unacceptable for a different group, because usability means that the site is “usable” for a specific set of users to accomplish a particular set of tasks. There are some basic guidelines that cut across all sites/web applications which are mentioned in this report, however to make a site truly usable all of the experts agree that it is the usability testing that is key to discovering and designing/redesigning a website/application to make it usable.
In his article “Usability 101: Introduction to Usability” Jakob Nielsen states:
Usability is a quality attribute that assesses how easy user interfaces are to use. The word "usability" also refers to methods for improving ease-of-use during the design process.
Usability has five quality components:
• Learnability : How easy is it for users to accomplish basic tasks the first time they encounter the design?
• Efficiency : Once users have learned the design, how quickly can they perform tasks?
• Memorability : When users return to the design after a period of not using it, how easily can they reestablish proficiency?
• Errors : How many errors do users make, how severe are these errors, and how easily can they recover from the errors?
• Satisfaction : How pleasant is it to use the design?
The most striking truth...is that zero users (tested) gives zero insights.
As soon as you collect data from a single test user, your insights shoot up and you have already learned almost a third of all there is to know about the usability of the design. ( Go to graph from Nielsen's report .)
Nielsen's report notes that even though you may need to test with 15 users to find 100% of all usability problems, you will find over 85% of the problems with just five users. After finding the problems with the group of five and doing a redesign, a retest with the five-user group will bring your discovery of overall usability issues to close to 100%.
Since no one can design the perfect user interface, sometimes two or three retests will be necessary to find and fix new design elements that may have usability issues.
Usability testing should be incorporated into the design process and performed by staff members of the design team. There is a mistaken notion that usability testing needs to be out-sourced and it needs to be expensive when in fact neither one will necessarily give you the results you are looking for. Adaptive Path partner Lane Becker states in his article “90% of All Usability Testing is Useless” says:
There is an outdated notion that usability research requires a blank slate—that outside observers will somehow comprehend what your users are doing in a more objective manner than yourself. But when you can't rely on statistics, and you need to understand the context of your site's use, all you have to go on is what you yourself can observe.
So it's time to get your hands dirty. Usability testing for the Web doesn't require outside firms that hold themselves separate from the design process. Understanding context means embracing this research as part of the design process.
One of the biggest obstacles to incorporating usability guidelines and practices into a website or web application you would think would be the time it takes or lack of expertise, when in fact it seems to be the perception by managers that it needs to be something expensive; and the lack of support for usability practices at the management level. Top usability experts agree that even with a very small budget and a few trained staff you can net significant gains in usability. In an article on “Usability is not a Luxury”, Donald Norman and Jakob Nielsen point out:
Usability is not a luxury on the Internet. It is essential to survival: it is the key technique for superior customer relationships. Remember, because switching costs are so low, attention to usability increases the percentage of those who actually complete a purchase after visiting the site. It's a lot cheaper to increase the human-centered design budget than to double the advertising budget. The Internet obeys a kind of Sheer Design Darwinism: survival of the easiest.
• Watch what people actually do.
• Do not believe what people say they do.
• Definitely don't believe what people predict they may do in the future.
The more a design supports users in easily and efficiently doing what they want to do, the more they like the design.
To test usability, you do not want to give a show and tell of the proposed design to a large group using a slide show or overhead presentation. Usability has to be tested by users preferable on a working prototype using the system as they would use it to do a job function. In an article titled “Usability 101” Nielsen states:
User testing is different from focus groups, which are a poor way of evaluating design usability… to evaluate interaction designs you must closely observe individual users as they perform tasks with the user interface. Listening to what people say is misleading: you have to watch what they actually do.
• Carefully observe the user group as they perform their predefined set of tasks (script) and record instances where they failed/succeeded.
• Capture the user comments at the time of their testing with a brief survey tool.
For content that needs to be printable, provide an easy way for users to get to a printable version or send a printable version to their default printer. Some usability features to consider are: page formatting to make sure the content fits on the printed page; printing the content only, not all of the related page design, navigation, buttons, etc.; showing the source on the top of the pages along with the page title; giving the printed pages page numbers.
ADA testing should be done along with usability testing to make sure that the design has options that make the functions accessible to those with disabilities and to make sure that a disabled user can use the system. The design can either offer the accessible options for all users or offer a special accessible mode that can overcome accessibility problems for a wide range of disabled users however, one of these options must be incorporated and testing for compliance must be incorporated into the overall system tests. Refer to a report on ADA Web Accessibility, June 2004.
The rule of threes still applies here as it does with other elements in a good overall site design (fonts, colors, graphics, etc.). In an article from Adaptive Path, partner Indi Young explains why three:
Good navigation and site design can net big benefits in worker productivity. In one study a large company with one of the least usable designs spent $3,042 annually per employee to cover time spent on sixteen tasks. In contrast the same company with an average usable site would spend $2,069 per employee per year, and a company that was among the best in usability would spend $1,563. For a company with 10,000 intranet users this translates to 30.4 million, 20.7 million and 15.6 million respectively.
Consistant, persistant design play a big role in site usability. Users get confused and have trouble adjusting to a drastically different look and feel for different division/section web pages. Ericksen notes in his article “Intranet Usability: The Trillion-Dollar Question”
Some intranets made an excellent effort, providing mostly consistent page appearance and navigation across the intranet. But, for many intranets, lack of consistent navigation was a big issue. Users had difficulties using the inconsistent designs and the drastically changing look-and-feel of different department pages. A small, persistent set of global navigation controls was helpful when available, as were breadcrumbs.
Many of the oldest recommendations for Web usability turned up again in the intranet study: links and buttons must be highly visible for clickability, and links should be color-coded to indicate when they lead to pages that the user has already visited. Violations of these two guidelines caused substantial navigational confusion; users overlooked choices or went in circles because they couldn't see where they'd been before.
Intranet navigation should serve a dual purpose : First, and most important, it should support task performance and give users access to tools and content. Employees should not have to know which department supports which features, nor should they have to navigate according to the organizational chart. Second, because people sometimes do need information about departments and company organization, you should provide navigation via an org chart as well.
In particular, information about departments such as human resources and IT should be segregated from the task-oriented information they provide employees. Users should be able to find the HR and IT tools they need in a task-based information architecture that resides outside the department hierarchy.
Nothing turns a visitor to a website off quicker than going to a page that is poorly written, or badly out of date content. Things like a calendar of events where the most recent entry is 6 months old, organizational charts that still list people who have retired years ago, or even more dangerous erroneous program or statistical data. Since the content is the “message” of the site it is important to devote adequate and appropriate resources to developing and maintaining it. In his article on “Ten Best Government Intranets” Jakob Ericksen gives these strategies to help manage content:
Leading experts are quick to point out that one of the keys to a successful site is to structure the site based on task support and not on organization structure. One large retailer netted big benefits by organizing their products by their function (like moving camping clothes, supplies, furniture, and accessories together).
For someone who has done website and web application developing for many years some of the concepts for usability seem to be second nature. Like sitting down with site users and asking them what they want, developing based on their requirements, and reviewing with them to see if they got what they expected and then refining as usability issues arise. Good clean design and listening to and responding to the users have been key to the development of agency websites and web-based applications.
For those who have not been exposed to this type of development, one of the biggest changes is in the level of listening that is required. Granted for any exchange of information to take place both sides have to be willing to give open, honest feedback; but even more than that, users have to trust that their business needs will be heard and addressed in the design. A total culture of usability has to be nurtured in an organization which includes frequent user testing (once or twice a month, in maintenance), training staff to do the user testing, quickly incorporating the design changes into the overall site. In an article on The Culture of Usability, Janice Fraser sums up the cumulative benefits thusly:
Usability is most effective when it's a low-stress activity that has become routine, rather than a special event that requires a lot of attention. It's best when it's like breathing, not surgery.
To begin developing a culture of usability, conduct small, focused, low-cost user tests very frequently. There's a special kind of economy of scale at work here. Over time, the team will come to value the tests as an essential part of the product development process.
With this approach, a larger group of people shares deeper insights over a longer time period. Product refinements become more effective each month, and your customers will feel the cumulative benefit.
As long as we have been developing web sites and web applications, the thing that is always core to the development is input from users and peers. Starting with the whole process of System Development and working thru gathering the information on what the site or system is suppose to accomplish and what the users expect, listening is the key. The next step is being able to take that information and develop strong prototypes and a layout (story board) of the flow using the guidelines in this report, ADA guidelines, and SRS web page guidelines. Then the most important step, the one where you find out whether you have been successful in your design, is to do usability testing.
Usability testing should be done as soon as there are drawn (hard copy) mock up of the system/site and should be scheduled regularly thereafter. In the development process this could be as frequent as weekly or bi-weekly but at least monthly.
useit.com (Jakob Nielsen et al)
Designing Web Usability – The Practice of Simplicity (Jakob Nielsen)
An Introduction to Usability (Patrick Jordan)
Usability for the Web (brink, gergle, & wood)
adaptivepath.com