Usability guru, Jared Spool, recently published an article on Five Usability Challenges of Web-Based Applications. He cited Facebook’s Beacon debacle where users are able to find out what their friends are up to.

Usability Challenge #1: Scalability
The number of users affected and the amount of information thrown at users are issues. “Designers need to take both the scale of the user base and the scale of the data into account when thinking about how to design their web-based applications effectively. A contributor to Facebook’s mini-feed debacle was the scale of their design. Facebook, making any change to their site, instantly affects eight million people. If even one percent has issues with the change, that’s 80,000 affected users. Being a social networking site compounded Facebook’s issue. Users connect to other users, some users having dozens or even hundreds of connections. Those users with many connections instantly saw a very populated mini feed and realized their previously subtle interactions on their page were now broadcast to each connection.”

Usability Challenge #2: Visual Design
“Sometimes, in web application design, it feels like every pixel matters. This isn’t just a question about the application’s aesthetics. Visual design can have a huge impact on how the application communicates its use. Yet, if the visual design isn’t clear and concise, the design takes the user’s focus away from what they wish to think about and forces them to try to guess what the designers were trying to tell them. Visual design problems affect an application’s success in a variety of ways. In the mildest form, they slow users down and distract them from their task. In the worst cases, they confuse users to the point of giving up or needing assistance. If the application is in the organization’s revenue stream or helps reduce costs, we’ve seen visual design issues can dramatically affect the bottom line.”

Usability Challenge #3: Comprehension
“Potential investors use the MSN Money Stock Research Wizard to help determine if a stock or mutual fund is the right investment for them. Because MSN Money tailored the wizard to new investors, the application contains detailed explanations, not only about the stock the investor inquired about, but about the questions the investor should be asking. Even if the application functions properly, it will fail the user if they don’t understand the information it’s trying to tell them. The investor needs to both use and comprehend the wizard for it to succeed. Web-based applications often help people by doing things outside their expertise. They turn to the application to help guide them through a decision making process they couldn’t do on their own. Yet, if they make the wrong decision, it negatively affects their experience and their relationship with the organization.”

Usability Challenge #4: Interactivity
“One of the big differences between a web application and other types of web pages is the user is far more interactive. On a content-rich site, users mostly click links and occasionally search. Yet, in a web application, they enter data, sort it, rearrange it, and move back and forth through the screens. Understanding how the user will manage their time becomes critical. Does the team put all the data entry on one long screen? Do they break it up across multiple screens? What is the logical order to enter the data? Users don’t always follow the “happy path.” They enter data incorrectly. They decide they need to go back and change something they’ve already entered. They discover they need to learn more about what the application is asking of them and, thereby, need more detailed assistance. Something as simple as always providing a mechanism to “undo” what’s already been done can create interesting usability dynamics. Handling how the application deals with browser controls, such as the back button, can make the designer’s life more challenging.”

Usability Challenge #5: Change Management
“The designers at Facebook learned the hard way that quick changes to the application, even if the team thinks it’s an improvement, can have serious negative results if done incorrectly. We all know that users are resistant to change, yet designing how the change will happen is often overlooked, to serious detriment of the user experience. While users are resistant to change, they are willing to do it when given enough support and structure. The problem with quick changes often happens when users frequently use an application and the old design conditioned them to things being a certain way. Even when the change is to their advantage, they often need warning and support to go from the old to the new. We’re now seeing teams start to design the change process along with designing the changes themselves. Paying attention to how users make the transition can increase a change’s adoption and build long-term user loyalty.”