Using the heuristic evaluation to improve the usability of the eCommerce

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It is called heuristic evaluation and is a method developed in the 1990s by Danish computer scientist Jakob Nielsen to simplify design research in a user interface and, in particular, critical issues in Web site usability.When applied effectively, its principles can help us in identifying and solving the burdens that hinder our eCommerce and achieve the desired goal of rapidly increasing sales.

What is the heuristic evaluation

Heuristic evaluation is a process of examining a user interface, such as a website or app, based on established usability principles, known as heuristics or general rules, that have been developed through years of research and practice in the field of usability. Evaluators judge the design against a set of guidelines (called heuristics) that make systems easy to use, with the ultimate goal of identifying interface problems so they can be solved and thus improve the overall user experience.

In the digital age, the success of an ecommerce business depends largely on the quality of the user experience, both in terms of success with the public and, increasingly, also in terms of ranking on Google, if we think, for example, of the attention given to Core Web Vitals and Page Experience: one of the most effective techniques for optimizing this experience is precisely the heuristic evaluation, a method of usability inspection that allows us to identify potential problems in a website.

The inventor of this process was Jakob Nielsen, known for his focus on the issue of website and application usability (as well as for his battles against the use of Flash technology or other heavy elements on sites), who in 1994 drafted a decalogue that remains a reference in the field to this day.

His heuristic evaluation method is a collection of usability guidelines, applicable to any interface, that are used to make of products and services that reflect the major standards in the field and thus ensure the best user experience for site visitors.

The expression harkens back to the term heuristic, which is proper to philosophy and the scientific method: the word is derived from the Greek verb meaning to discover or search, and is used to denote “a set of inventive strategies, techniques, and procedures for searching for an argument, concept, or theory adequate to solve a given problem.” In short, these are general rules of thumb, not specific usability guidelines.

Nielsen’s 10 heuristics for user interface design

It is appropriate at this point to dwell on these 10 heuristics identified by the Danish computer scientist almost 30 years ago now, still valid today despite the extraordinary evolutions in technology.

These are fundamental principles in the field of user interface design, high-level rules of thumb based on an understanding of human behavior, psychology and information processing. Here are Nielsen’s 10 heuristics that, when applied correctly, can help significantly improve the usability of a website or application.

  • System status visibility. The system should always keep users informed of what is happening, through appropriate and timely feedback.
  • Correspondence between the system and the real world. The system should speak the users’ language, with familiar words, phrases, and concepts rather than system-oriented terminology.
  • User control and freedom. Users often choose system functions by mistake and need an emergency “way out” to leave the unwanted state without having to go through a lengthy process.
  • Consistency and standards. Users should not have to guess whether different words, situations, or actions mean the same thing. Follow the conventions of the platform.
  • Error prevention. Even better than excellent error messages is careful design that prevents the possibility of error upstream.
  • Recognition rather than remembrance. Make objects, actions, and options visible-the user should not have to remember information from one part of the dialog to another.
  • Flexibility and efficiency of use. Shortcuts and accelerators, invisible to the novice user, can often speed up interaction for the experienced user; it may be useful to allow people to customize frequent actions.
  • Aesthetics and minimalist design. Interfaces should not contain irrelevant or rarely needed information: each extra unit of information in an interface competes with relevant units of information and decreases their relative visibility.
  • Help users recognize, diagnose and recover from errors. Error messages should be expressed in plain language (no codes), state the problem precisely, and constructively suggest a solution.
  • Help and documentation. In the ideal situation, the system can be used without documentation: however, it may be necessary to provide help and documentation in a way that is easy to search and not too voluminous, with content focused on the user’s task and separated into concrete steps to be performed.

As Nielsen himself recounts, the evaluation heuristic was initially developed in collaboration with Rolf Molich in 1990; four years later, the Danish expert refined the heuristic based on a factor analysis of 249 usability problems to derive a set of heuristics with the highest explanatory power, which are precisely the set just presented.

In 2020, the list was updated both in the language of definitions and with additional explanations, examples and related links, but the 10 heuristics themselves have remained relevant and unchanged since 1994.

When heuristic evaluations are needed

Heuristic evaluations are useful for identifying obvious problems in an interface: by this term we can identify virtually anything that users will interact with, including prototypes, physical products, games, virtual reality or voice interfaces, as well as, of course, websites and, as we shall see, particularly e-Commerce.

This method can be particularly useful at the beginning of the design process, to find likely problems without having to test directly with participants, but they cannot replace field research performed by real users. User-experience design is in fact highly contextual, warn the experts at Nielsen Norman Group, and so to actually design good experiences, testing with real users is still necessary, and integrating heuristic evaluations into the team’s research work: for example, performing a heuristic evaluation in preparation for a subsequent usability test could help you identify design elements to focus on during testing.

Conducting heuristic evaluations is also a good way to develop strong UX instincts and train yourself to detect common usability problems.

How to do a heuristic evaluation, a quick guide

The first step in conducting a heuristic evaluation is precisely to define the heuristics, or usability principles, that we are going to use.

The second step is to select the usability experts who will conduct the evaluation. Unlike other usability testing methods, the heuristic evaluation does not require a sample of users, but rather experts who examine the interface, who using the heuristics as a guide will be able to identify and point out problems found on the site or app, such as lack of consistency or poor system visibility.

The number of experts can vary, but it is generally recommended to have at least three or four experts to ensure adequate coverage. At this stage it is very important to set the scope of work: the narrower it is, the easier and more detailed the evaluation will be. And so, for your team’s first heuristic assessment or in case of a large and complex product, the suggestion is to narrow the scope to make things manageable by limiting the observation to one task, one section of the site or app, a specific target user group or device type (desktop, tablet, mobile).

After identifying the experts, the next step is to perform the evaluation: as a rule, it is suggested that the experts work separately, leaving each one free to examine the interface autonomously and independently to avoid mutual influence, looking for and pointing out usability problems and then comparing and discussing the results with the other experts.

In fact, at the end of the individual evaluations, the results should be compared and discussed: in this way, it becomes easier to identify the most serious problems and set priorities for corrections. During this discussion, experts can also share their different perspectives, which can lead to a deeper understanding of usability problems.

Finally, corrections should be implemented, which can range from changing the interface design to adding new features or updating the documentation. The last step might be to conduct another heuristic review evaluation to make sure that the problems have actually been fixed.

Practical applications: how to make a heuristic evaluation of an eCommerce

In a context where time is essential, being able to solve usability problems by conducting an effective heuristic evaluation means being able to turn our online store around and improve sales almost immediately.

Thanks to these principles we will discover the main problems that undermine the site as they make the lives of customers complicated, so much they prefer to turn their attention elsewhere. The advantage is that this health check of the project does not need a long and exhaustive study, because you need to examine every detail but just focus on a general overview of the most known usability factors that affect sales.

Also, the other useful feature of this study is that problems, once identified, are fairly intuitive and simple to solve.

We will not find all the problems and errors of the site, but we will have a new vision and a set of actions to take immediately to turn and improve sales.There are three steps that guide us to the realization of an effective study on the usability of the site, as suggested by Kayle Larkin on searchenginejournal:

  1. Recruiting
  2. Rating
  3. Analysis

Three steps of the work

The work begins by identifying a small group of team members (3 or 5 people) who can participate in the project as site evaluators. They do not need to have specific skills in web design or search engine optimization, more than that, it is good to recruit diverse experiences and skills to have multiple eyes on the matter and better results.
The practical part begins: each member of the team will have the task of inspecting the website in an independent and autonomous way, so as to ensure the impartiality of each evaluation. We do not have to talk about the progress of the project until the study is complete.
The last step is the analysis of the results, which we can perform in two different and equally functional methods

  • To register the single evaluator

You need to find a general project manager who collects and live records the evaluator’s comments while interacting with our website. This method increases the overload of each evaluation, but reduces the workload on individual evaluators.

The results will be available quite quickly as the observer only needs to understand and organize his own set of notes.

  • To gather reports written by each evaluator

The second path is longer as it requires the creation of written reports by each participant (which is then asked for an additional effort), that provides a formal recording of the studio. The person in charge of the bill aggregates all the notes, thus creating a final report.

Usability principles

Now we come to the practical part of the heuristic evaluation, referring to the methodology developed by Jakob Nielsen more than a quarter of a century ago now. The Danish computer scientist has outlined 10 general rules which can describe the common properties of the various usable interfaces, that we may use as guidelines to add further considerations on the user experience that come to mind during the evaluation of the individual website.

These principles also apply to online sales sites and, as we will see, they are not too far from the ecommerce optimization techniques that we had seen not long ago.

  1. Feedback

Technically referred to as “visibility of the system state“, is an invite to keep users informed about what is happening: every person on the site should, at any time, know what area is located, at which stage of the purchase process and what you need to do to proceed. Specifically, eCommerces can take care of this by intervening on:

  • Clear and recognizable logo in the header.
  • Description of the value proposal.
  • Clear Call to actions.
  • Clearly marked shop.
  • Easy navigation options to follow.
  • Checkout viewable from all pages.
  • Easy-view cart
  • Progressive counting of products in the cart.
  • Indication of the total value of the purchase.
  1. Contact with the real world

Nielsen invites us to verify and take care of the system’s correspondence with the real world, that is, to use the user’s language and words, sentences and concepts that may be familiar to him. Moreover, even the flow of online shopping sites should reflect the scenarios of the physical world, and so you have to:

  • Use a user-centred language.
  • Use a useful and descriptive language.
  • Do not use any slang.
  • Make the images scroll from right to the left.
  • Recreate the virtual experience offered in the store.
  1. Freedom

Users need a clearly marked “emergency exit” when they click on an item by mistake; in practical terms, we must allow operations to be reversed and restored so to give customers freedom and control over what they are doing. Other specific suggestions are:

  • Enter product reviews before checkout.
  • Ability to easily remove items at checkout.
  • Possibility to change quantity at checkout.
  • Possibility to change the type/color of the product at checkout.
  • Possibility to cancel or modify the orders after the purchase.
  1. Cohesion and consistency

The conventions of the system must be valid along the entire interface path, says Nielsen; this means that users should not have the doubt that different words or actions can mean the same thing. For this, we suggest using established standards such as “add to cart” buttons or sliding images to reduce confusion and increase efficiency, and then again:

  • Use recognizable CTAs as “Buy now” or “Add to cart”.
  • Use a basic format or template.
  • Use large images.
  • Insert short product descriptions.
  • Use visual CTAs.
  • Insert reviews at the bottom of the page.
  1. Errors prevention

A careful design can prevent the possibility of an error by users, avoiding the creation of ambiguous or critical situations for customers. Basically, for an eCommerce this applies in:

  • Real-time validation of forms.
  • Simple instructions on how to correct an error.
  • Recommendations for out-of-stock or unavailable products, strategically using 404 error pages for example.
  1. Recognition and memory

The invite is to make objects, actions and options as intuitive as possible, so they can be easy to use and remember. We can use a web design that users already know about (as is the case with Amazon-based models), or avoid requiring users to retrieve information from a previous interaction, and then again, on the practical side:

  • Grid layout.
  • Logo on the top left.
  • Top right cart button.
  • Menu with dropdown categories.

In this regard, however, it is important to reason about one aspect: just because a design choice violates a heuristic does not necessarily mean that it represents a problem that needs to be solved, because it all depends on the particular context and available alternatives. For example, hamburger menus theoretically violate heuristic #6 but often, in mobile applications, they prove to be a necessary compromise because of the small screen space. This is a great example of why, as we said earlier, heuristic evaluations are not a substitute for user research, but we still need to observe our users as they use our products to fully understand the design issues.

  1. Flexibility

The efficiency of the site increases if users can set preferences and interact with the system in the way most appropriate to them. We can achieve the flexibility of use with some methods:

  • Account creation.
  • Possibility to indicate favourite items.
  • Possibility to save items in a shared list.
  • Possibility to save the delivery information and the chosen payment method.
  • Possibility of payment through multiple systems.
  • Automatic fill-in on payment forms.
  1. Minimalistic design

Nielsen invites us to give more emphasis to the content than to the aesthetics: this means that we must include in the Web page only what is necessary, because any other information element is to attract the attention of the user, which then distracts you from what should be the central message sent by the site. The practical tips are:

  • Use a mobile-friendly design.
  • Limit the visual disorder.
  • Draw attention to the main image.
  • Draw attention to the description.
  1. Support to the user

We all make mistakes and the task of a site is to help the user to recognize, diagnose and recover what has been done. We must then clearly highlight the problem and offer a solution with some steps:

  • Highlight errors in red.
  • Clearly define the error.
  • Offer a solution.
  1. Documentation

Every site, and in particular every eCommerce, must allow the users to find the documentation and to simplify the search of help information, also through the systems of specific assistance. The techniques to apply this principle are simple:

  • Provide easily identifiable and accessible help documentation.
  • Allow contact with customer service.
  • Insert a link to the FAQ in the footer.
  • Insert a set of Q&A (questions and answers) into the product pages.

In the background, then, we should not forget that there are exceptions to these heuristics, although they are usually rare and context-based. Heuristics remain guidelines, not laws, and there are some cases where it may prove necessary to violate one heuristic in order to pursue another goal (as in the case of hamburger menus). However, as Jakob Nielsen says, we should not “bet that our design is one of the few exceptions”: before deciding to intentionally violate a usability heuristic, therefore, user research should be conducted to ensure that the rule violation is actually justified.

Ultimately, the evaluation heuristic is an effective method for identifying and solving usability problems even of a website or application. It requires an investment of time and resources, but the benefits in terms of improved user experience can be significant.