The first of Jacob Nielson’s 10 useability heuristics is visibility of system status, this heuristic refers to how well the state of the system is conveyed to its users. Systems should always keep users informed about what is going on through appropriate feedback within a reasonable time. Imagine waiting for an elevator. You press the call button and expect it to light up to reflect that the system knows you’re waiting and will send an elevator soon. You might even be able to see what floor that elevator is currently at so you can gauge how long you’ll need to wait. That knowledge is power. Open communication between the system and the user not only allows you to understand what is happening, but also empowers you to make decisions based on that information.
Consider what information about a system the user needs to know and present that to them in a timely manner. This system status could be persistent or always visible, like a battery life or Wi-Fi connection indicator. Or it can be feedback that is only shown after the user has done something just like when pressing that elevator button. Feedback is critical to let people know their interactions with the system were acknowledged and successful on a website or app. We expect visual feedback when we click an element which can be as simple as changing the button color and, where appropriate, displaying a progress indicator. People should feel confident that their click was recognized and that the system is now working on the request. Understanding a system’s current state is all about allowing users to feel in control. That said, providing visibility into the system does not mean you need to tell the user absolutely everything the system is doing. Don’t provide system status updates. If the user can’t do anything with that feedback anyway, too much information is distracting. So focus on only those key pieces of information that will truly be helpful or provide reassurance to the user.
The visibility of system status heuristic highlights the importance of open and continuous communication, which is fundamental to all relationships, whether with people or with our devices. It’s the key to making a system feel reliable and predictable, which in turn creates trust.
People shouldn’t have to wonder whether different words, symbols, situations or actions mean the same thing. We can think about two types of consistency as it applies to you. UX design, internal consistency and external consistency. Internal consistency refers to maintaining consistency within a product or a family of products. For example, maybe your visual designers decide to use a specific shade of orange to highlight actionable elements, things like call to action buttons. If you decided to then use that orange to highlight a static heading, you’d be breaking internal consistency. That might be a problem because it violates the established meaning of that visual treatment.
Users may no longer be able to rely on it to help them determine which elements in your UI are actionable. External consistency refers to maintaining consistency outside of products. You might have established conventions for you guys in your industry or even established conventions for you guys in general. For example, most ecommerce sites have a shopping cart feature. People are familiar with this feature because they see it any time they use an e-commerce site. They have existing expectations for how that feature should work and where it should be placed in the upper right corner of the screen. Usually Jacobs Law can help us to understand why external standards are so important. Jacobs Law states that people spend most of their time on sites other than yours. If all of those other sites follow a consistent convention, but your site breaks that convention, you’re forcing people to learn something new.
There are times when breaking conventions can be worthwhile. Maybe you just figured out a new and better pattern. Just remember, you’re adding to your user’s cognitive load every time you make them learn something new. So you should only do it when it’s absolutely necessary. In most cases, it’s best to maintain consistency, both internal and external, to improve your products learnability.