Een introductie in usability: Wat betekent het en wat kan het voor jou doen?

Usability is determined by 5 elements:

1. Learnability

How easy is it for the user to use their target the moment they first encounter the design?

2. Efficiency

Once the user knows the design, how quickly can they perform their tasks?

3. Memorability

If the user has not used the design for a while and they return, how easy is it to use the product again?

4. Errors

How many errors does the user make, how serious are these errors and how easily can the user recover from the error?

5. Satisfaction

How pleasant is it to make use of the design?

Usability versus Utility

There are more elements that determine the quality of a design, namely 'utility' - the usefulness of the design. Does the design do what the user needs? The utility of the design is at least as important as usability. After all, you have no use for a design that is easy to use but does not do what you want. Conversely, it's also no good if the design can basically do what you want, but you can't get it done because it's too difficult. To investigate the utility of a design, you can use the same methods you use to investigate usability.

Why is usability important

On the worldwide web, usability is a prerequisite for survival. If a website is difficult to use, people will click you away in no time. If your homepage does not make it clear what you offer as a business and what you can do on the site, people will click away. If visitors get lost on your site, they click away. If the information on your site is hard to read or doesn't answer the visitor's question, they will click away. So don't think your visitor is going to bother or spend time figuring out how your website works. If visitors experience a problem they are just as easily gone again, after all, there are plenty of other sites. Rule number one of e-commerce is that if people can't find something, they can't buy it.

Usability and intranet

For intranets, usability is about employee productivity. The time employees spend getting lost on the intranet or having to think about difficult instructions costs you money as a company.

Doubling conversion

Best practices tell us to spend about 10% of a design project on usability. On average, this will double the conversion of the site, in the case of an intranet just slightly less. For software and physical products, the improvements are usually smaller, but still significant if you include usability in the design process. When it comes to conversion, for example, think of doubling sales or doubling the number of registered visitors.

How to improve usability

The simplest way to research usability is to do user research. This kind of survey has 3 components:

1. Make sure you have representative respondents, such as real customers if you want to test an e-commerce site.

2. Ask the respondents to perform representative ('real') tasks.

3. Observe the respondents. See what they do, what makes them successful and where problems arise. Keep your mouth shut and let the respondent do the talking.

It is important that you let respondents test individually and solve their problem themselves. If you help them or point them to a certain part of the screen, you influence the test.

Five respondents is enough

To get the main bottlenecks from design, testing with five respondents is enough. Do small practical tests several times rather than a large, expensive survey. The more versions and ideas you test with users, the better.

No test panels

Setting up a test panel is not an appropriate way to measure usability. Test panels can be useful in market research, but when evaluating a design, you need to observe its individual use. Listening to what people have to say is misleading in this case: instead, you should observe what they actually do.

Where in the design process do you engage with usability

Usability plays a role at every stage of the design process. The need for multiple surveys is one of the reasons Jakob Nielsen advocates quick and inexpensive surveys. Here are the key steps:

1. Test the current / old design before testing the new design. This will help you determine the good and bad elements of the design.

2. Learn from other designs that have pretty much the same features as your own.

3. Carry out a practical field study to find out how visitors behave.

4. Make paper prototypes of ideas and test them. Don't spend too much time on the idea; you may have to change it again based on the test.

5. Refine the ideas that test best through iterations, starting from a very simple and low-level prototype to a clickable on-screen design. Test each iteration.

6. Play the design alongside the usability guidelines.

7. As soon as you implement the final design, test it again. Usability mistakes always creep in during implementation.

Don't put off doing user research until you have a full final implemented design. The earlier you test in the process, the better. And above all, keep testing on the way to the final design.

Where are you going to test?

If you run user tests every week, it is worth creating a usability testing room. For most companies, however, it is more than fine to do the tests in a meeting room or an office. As long as you can close the door and work without distractions. It is important that you use 'real' respondents and sit with them at the time of testing the design. All you need is a notepad and a pen.