User Error Defined

How exactly is an error defined? An error occurs when a website or application fails to complete an expected action. In simple terms, it’s when the application doesn’t do what you want it to do. Errors are typically the result of faulty applications, websites, or user action. If the application isn’t coded properly or the user made a mistake, these errors will keep the application from working as it should.

When an error stems from user input, it is categorized as either a slip or a mistake.

  • A slip occurs when a user does something incorrectly without being aware of it. Most often, this happens when they complete an action without thinking and accidentally delete or select something they didn’t intend.
  • A mistake is when a user consciously does something incorrectly because they don’t understand what is being asked of them. Let’s say an application asks for temperature in Celsius, but the user assumes it is asking for Fahrenheit. Although the user enters the correct Fahrenheit temperature, the application output would be incorrect, since it is expecting the temperature in Celsius.

In this article, we will concentrate on three design strategies to help prevent user error, with a strong focus on slips. We will also review the importance of designing for different errors, provide simple questions you can ask during the design process, and discuss the importance of inline validation, intuitive design, and using friction.


Why Design for User Error?

Now that we understand the different types of user errors, it’s important to understand the benefits of designing for those errors. Experience design often concentrates on how to create designs that improve usability and accessibility for people. Yet, sometimes it’s important to create design features that are more difficult and add clicks as a way of reducing user error.

For those that use Gmail, you’ve likely seen the below message:

gmail file attachment error


Gmail scans email text looking for words that indicate there should be an attachment in your message. In this example, the phrase “find attached” triggered the error message to appear. While there may be instances where you had no intention of attaching a file, it is more likely you forgot to attach the referenced file and pressed “send”. This pop-up, while adding a step, gives you the time and information you need to recognize that you’ve made a mistake and correct it, preventing a slip.


Simple Ways to Prevent Errors

Before starting your design project, it’s important to consider the different errors that can occur as someone interacts with your website or application. For each action, consider if the following should or could be used to prevent user error:

  • Ask for Confirmation: If a user is completing a critical action, such as a permanently deleting a file, request confirmation that it is the intended action. Often, this adds more clicks for the user, but may alert someone who accidentally clicked “delete”.
  • Confirm the User’s Intention: If a user is trying to complete an illogical action, such as creating an invite for a date in the past, confirm the user’s intention. The user may be doing this on purpose, but they also may have meant to type in “2019” instead of “2009”.
  • Utilize Intuitive Design Principles: Designing with intuitive features such as appropriate color schemes and inline validation can prevent several errors early and often. For example, you wouldn’t design response messages with red to signal success or green to signal failure.


Designs that Prevent Slips

1. Inline Validation

Real-time inline validation immediately informs users about the correctness of the provided data. For example, if a birthdate is entered into an application that is a year in the future, the input will show up red. In real-time, the application notifies the user there’s an error that needs to be fixed before they hit “submit”.

Without inline validation, the user may fill out the entire form and hit “submit”, only to be notified of the mistake afterward and then forced to re-type the information. Having real-time validation is highly beneficial to the user and improves their overall experience.

Design for user error, Mobile App Inline Validation


2. Right Color + Clear Message (Intuitive Design)

While intuitive design doesn’t have an agreed-upon definition, it is essentially the ability to make your designs immediately self-explanatory and easy to understand. All elements of design, including color, messaging, and graphics, should be intuitive. Color can be a powerful element in design to signify errors, identify important items, and improve aesthetics, but it is also important to consider the symbolic nature of color. Red often symbolizes danger or a warning (think stoplights, stop signs, exit signs), while green evokes feelings of comfort and prosperity (e.g. nature, money). An intuitive design would use red to indicate an error instead of green since red is how we commonly associate something with being wrong or incorrect in our day-to-day lives.

Correct color & message in user design

Incorrect color & message in user design


When designing intuitive messaging, the human element is key. We’ve all received error messages with codes that we don’t understand. Instead of a pop-up with “error 425976_JB_12”, take the time to update the language used to notify someone of an error, including what the error is and the steps they can take to fix it. Also, take the time to consider who your users are and how to appropriately communicate with them. Designing an application for children aged 7-12 will likely require different messaging than an application used by an engineer.

3. Designing for User Error with Friction

Design friction is anything that prevents users from accomplishing the desired results. With people on the go and multi-tasking constantly, we don’t want to ask users “Are you sure you want to do this?” for every action they take, but in certain situations, it is beneficial to slow the user down by adding in that extra step to ultimately prevent errors from occurring.

Design for user error, macbook frictionDesign for user error, calendar & scheduling friction





In the examples above, the computer uses friction to make sure the user wants to take any action that it finds detrimental or confusing.

“Are you sure you want to permanently erase the items in the Trash? You can’t undo this action.”

In this case, the message is asking for confirmation and giving subtext as to why this action is potentially dangerous.

“The date of this event is in the past. Are you sure?”

In this case, the message is confirming the user’s intention, pointing out that this action seems illogical (even if it is intentional). This doesn’t mean the user can’t take the action. It is simply intending to help prevent an error. Ultimately, friction saves people time, improves their experience, and builds credibility.

By anticipating errors and strategically placing friction, we prevent accidental transactions, errors in messages, or the deletion of important files, and show users that we have designed with their best-interest in-mind. In fact, a lack of friction can create distrust in applications. The Wells Fargo mobile banking app incorporated an “eye skating” security feature that scans and authenticates your eye print as a way of unlocking the app. Users of the app felt that the scanning and validation happened too quickly and that there was no way it could work that fast. Because of this, developers eventually increased the delay time to assuage those doubting its effectiveness. 

Wells Fargo eyeprint authentication


User Error on Digital Platforms

When designing, it’s important to remember the human element and the ultimate truth that humans make mistakes. Every application and digital platform can be improved by anticipating those mistakes and prevent them from occurring. It’s a great reminder to your customers, partners, and employees that you have their best interest in mind and that you are providing them with the best tools available.

Remember to ask simple questions throughout the design process to keep these errors in check, and use friction, inline validation, and intuitive design strategically. Finding the correct balance of these elements is important for good user experience, and if done correctly, will accelerate your designs and application to the next level.

Sense Corp is a leading professional services firm transforming organizations for the digital era. We help clients solve their toughest challenges by bridging the gap between what is and what’s possible. To learn more about the services we offer,  contact us.  

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