Usability

Usability is a central term in user experience design. This article deals with the question of what exactly is meant by the term and which aspects play a role in user-friendly digital products.

How can usability be described in essence? Let’s start with an explanation of the term, which can be found on Wikipedia:

Usability refers to the quality of use experienced by the user when interacting with a product, system or service.

Source: Wikipedia

User-friendliness therefore describes how well a (digital) product can be used by users.

Admittedly, this is a very limited description of what is meant by the term user-friendliness. The following therefore deals with different aspects in order to better understand the topic of user-friendliness.

There are always terms circulating around the topic of usability, some of which mean the same thing but are different in detail. Two of these are the terms user experience and accessibility.

A key aspect of good usability is the quality of use. It can be used to describe how a product can be used by users. Three basic usability criteria can be used for this purpose:

Effectiveness, efficiency and satisfaction.

These three usability criteria all have a direct influence on the quality of usability of a digital product – in other words, on the quality of use.

Effectiveness describes how well a system, product or service supports users in achieving their intended goals. It is measured by accuracy, i.e. the extent to which the actual result corresponds to the desired result, and by the completeness of the results. The latter shows whether all intended results can be achieved by using the system. For example, whether users can use the search function to find a product in an online store.

A helpful measure for determining completeness is the success rate: the ratio between the number of users who successfully achieve a certain goal and the total number of those who attempt to achieve the goal. Overall, effectiveness reflects how well a system enables the completion of tasks and thus increases user-friendliness.

Efficiency refers to the ability of a system to accomplish a task with minimal use of resources. These resources include time, human effort and financial and/or material resources.

A system is considered efficient if users can achieve their goals with as little effort as possible. For example, if users can place an order via a quick purchase button without having to go through the shopping cart.

Efficiency is therefore a decisive attribute of usability, as it directly influences how quickly and easily a task can be completed. An efficient usage concept and/or design helps to increase user-friendliness by optimizing the usage process and removing/avoiding unnecessary hurdles.

Satisfaction describes how pleasant and positive the use of a system is for users. It is influenced by both effectiveness and efficiency: if a system is not effective or efficient, this can reduce satisfaction.

At the same time, a high level of satisfaction can improve effectiveness and efficiency, as satisfied users are more motivated to complete tasks successfully. Purchase incentives, such as discounts or extras, for example, can have a positive influence on user satisfaction.

User surveys are an effective way of measuring satisfaction. We often see these surveys after the introduction of new functions in an app, for example.

Basic criteria in practice

Whether and how the basic criteria can be met during use depends on various factors. For example, if the goals of users vary or are unknown, this can affect the usability of a product, as it sometimes cannot be tailored precisely to the users.

The context of use, i.e. the setting in which a product is used, also has a significant influence on usability. For example, if a smartphone app is primarily used outdoors (in the sunshine) and the color contrast in the interface is too low, this can impair the effective usability of the app.

In addition, technical defects can also impair usability by preventing users from completing their tasks effectively or efficiently. In such a case, one speaks of a usability problem.

The three usability criteria—effectiveness, efficiency and satisfaction—are therefore essential for comprehensively evaluating the user-friendliness of a digital product. They help to assess the quality of a system from different perspectives: Can a goal be successfully achieved (effectiveness)? How easy and resource-saving is this possible (efficiency)? And how positively do users perceive the entire process (satisfaction)?

By considering and optimizing these criteria, a user experience can be created that not only meets users’ needs but also exceeds their expectations, which ultimately improves the overall user experience.

Another important aspect in the user-friendly design of (digital) products are Jakob Nielsen’s ten usability heuristics. He developed the principles for interaction design back in the 1990s in order to design systems in a more user-friendly way.

These guidelines still help UX designers today to consider usability from the outset and thus avoid typical usability problems.

The system clearly informs users about the current status, e.g. by means of a process bar (loading bar) that shows the saving process of a document.

The design speaks the language of the users and uses familiar expressions and concepts. For example, users place their goods in the shopping cart or shopping basket in an online store. Both are metaphors from the “real world”.

Users should always have the opportunity to make their own decisions about their actions. For example, if they make a mistake in an ordering process, they should always have the option to cancel the process or go back through individual steps.

People are ‘creatures of habit’. It is therefore helpful for users to use familiar symbols, patterns and formulations. For example, the shopping cart symbol is an example of a standard that is understood inter-culturally by users. Consistency within a platform also helps visitors to find their way around.

When developing a digital product, the top priority should be to create a system in which users cannot make mistakes. To achieve this, it often helps to avoid complex and error-prone steps right from the start. Short help texts in a user interface (UI) support successful use.

Elements should be designed in such a way that users can easily understand their function or purpose. The use of recognizable design patterns, such as article tiles in a blog, also helps users to orient themselves within a digital product. Another example is the font selection menu in a text program. There, it helps users if not only the name of the fonts is displayed, but also what the respective font looks like.

There is rarely just one user or just one way. Flexibility is therefore essential for good usability.

It can often be helpful if users have several options for achieving their goal on a website. In the application environment, shortcuts can also help users to use an application even more efficiently in addition to the normal functionality.

A clear design that is reduced to the essentials makes it easier to use digital products. The Google page is a good example of this. An almost empty page with a simple input field gets users to their destination very efficiently—namely to start a search.

Unfortunately, mistakes are sometimes unavoidable. However, it is all the more important to provide users with the best possible support when solving problems.

Error messages should always be written and recognizable in such a way that they can be understood by users. For example, technical (cryptic) error codes should be avoided for most user groups, unless they can help solve the problem—for example, as part of a support request.

In addition, internationally recognized symbols and colors (e.g. red for errors) help to clarify the context non-verbally.

Ideally, a (digital) product can be used without additional explanation. However, easily accessible and comprehensible documentation can support users if necessary.

Jakob Nielsen’s ten usability heuristics offer a clear and practical guide to designing user-friendly digital products. They help UX designers to avoid typical usability problems from the outset and create a positive user experience.

Although they were formulated back in the 1990s, Nielsen’s ten usability heuristics are still relevant. They take into account basic human behaviors and expectations that have not changed significantly in the digital world. They provide a flexible framework that can be adapted for both simple applications and complex digital systems. Overall, the heuristics help to optimize user-friendliness and strengthen users’ trust in the product.

Usability is a decisive quality feature for digital products.

The user-friendliness of a digital product is significantly influenced by various aspects of its usability. The usability criteria described in the article—effectiveness, efficiency and satisfaction—provide a comprehensive basis for evaluating and improving the user-friendliness of a system.

By taking Jacob Nielsen’s ten heuristics into account, usability can also be planned with precision. The usability heuristics should always serve as a guide for designers to enable good usability for users.

Usability can also make a valuable contribution to barrier-free use and ensure that people with disabilities can also access a digital product.

Overall, it can be seen that a well-founded examination of usability and its related topics not only leads to happier users, but also promotes the success of a digital product in the long term.