User experience design applied to the creation of digital interfaces is a concept at the crossroads of user experience and two disciplines: ergonomics and design (or UI).
Even if user workshops and co-construction are 2 essential pillars of a successful user experience, laws and main principles established by renowned researchers, psychologists and ergonomists are essential to guide UX designers in their recommendations.
Like the magician revealing the secret of his tricks, we will reveal to you 10 fundamental laws for a successful user experience (and to shine in the evening)
1. Hick’s Law
Too much choice kills choice! We’ve all been faced with it: the more choices you are given, the more difficult it will be to make a decision. Limiting the number of choices as much as possible will save the user time and improve their perception of your interface.
2. Fitts’ law
Fitts determined that the time a user hovers over a graphic element varies depending on the size of that element.
Pay attention to the proportions of your CTAs and spaces!
3. Doherty’s Threshold
400ms… yes milliseconds… or 0.4s!
This is the reaction time of an interface during an action. Beyond that, the user (again) waits, gets impatient, and quickly goes berserk. Telling it to load by a loader will avoid this undesirable side effect.
4. Miller’s Law
We humans have a very low storage capacity (we say that but we haven’t tested cats).
7 is on average the number of objects or words that we can memorize.
Hence the importance of grouping information, particularly in navigation menus.
At the agency, we often use this law as an excuse not to overload navigations. “10 items on the menu? Sorry that’s not possible, Professor Miller said that.” Unstoppable.
5. The law of Pregnancy
So not only do we not retain much but we only retain simple shapes. Our brain is naturally lazy and interprets shapes by simplifying them. The simpler the shapes, the better they are remembered. This survival reflex allows the user not to overload their human cerebral cortex with useless information.
6. The law of similarity
We continue in the series “the human brain is lazy”.
The human eye tends to perceive similar elements in a drawing as a complete image, shape, or group, even if these elements are separate. The brain will create a link between elements of the same nature.
It is therefore important to clearly differentiate the elements of your interface according to their function to avoid confusion (between menu elements and content elements for example).
7. Jakob’s law
“Let’s not try to reinvent the wheel.” This old adage applies perfectly to certain recurring features on the web such as registration forms or payment interfaces (which we cover in a dedicated article).
It all depends on the theme of the site in question and the creative challenges of the project, but in case of doubt it is better to rely on good practices accepted by all. The user will gain understanding time for the benefit of the task at hand.
Again, their perception of your site will be reinforced.
8. The law of the common area
Do not confuse with the area of your municipality which defines the school calendar applied in your academy but it is just as simple to understand: All the elements located in a defined area (by a colored background or a frame for example) are considered as belonging to the same group by users.
For example, the navigation of a site can be identified by a background.
9. The law of unified connectivity
In line with the law of the common area, this indicates that all elements linked together via a line, a frame or a shape are perceived as a single unit by the user.
We’ll let you guess in which examples this law can apply (use a little imagination!)
10. The insulation effect
Also called the “Von Restorff effect” for short, it states that an object that stands out from others is more likely to be remembered. It thus generates a cognitive bias retaining what is unusual or distinctive. A slightly different CTA, a colored item in a list or even a pictogram thicker than these will suggest to the user the path to take.
