Visualisation of some of the 43 laws of UX
In my first story ‘User Experience is …’ I promised that …
"over the course of a few stories, I’ll try and cover a few of the sciences we draw upon in our art as a creative community to create engaging experiences."
And previously I’ve talked about Using Gestalt theory to improve the user experience and also how User Experience is … Psychology. But this time out I’m introducing a number of UX laws and how they can be used to improve the User Experience.
Visualisation of some of the 43 laws of UX
Here’s 7 laws that are so good the people who created them put their names to them. Not all the UX laws, but a good way of choosing some to write an intro on.
The time to acquire a target is a function of the distance to and size of the target.
Fitts’s Law was established to understanding human physical interaction and movement. It’s all about measuring the time or ease of interaction, which is made up of the distance needed to move and the size of the end interaction point.
In 1954, psychologist Paul Fitts, examining the human motor system, showed that the time required to move to a target depends on the distance to it and its size. Fast movements and small targets result in greater error rates, due to the speed-accuracy trade-off.
Fitts’ law can be used in UX and UI design, as guidance for size and positioning of interactive buttons. Larger buttons are better for touch devices as smaller buttons are more difficult and time-consuming to click. Also the distance between a user’s task/attention area and the task-related button should be kept as short as possible.
Simplify options to make decisions easier
The time it takes to make a decision increases with the number and complexity of choices.
Hick’s Law is named after a British and an American psychologist team of William Edmund Hick and Ray Hyman.
In 1952, Hicks and Hyman set out to examine the relationship between the number of stimuli and an individual’s reaction time.
Hicks and Hyman found that the more options, the longer it takes the user to make a decision on which one to interact with. Users bombarded with choices have to take time to interpret and decide, giving them work they don’t want.
Previous knowledge and experience helps people to know how to interact with familiar things
Users spend most of their time on other sites. This means that users prefer your site to work the same way as all the other sites they already know.
Jakob’s Law is named after the founder, Jackob Neilson of the Nielsen Norman Group.
Jakob Nielsen established the ‘discount usability engineering’ movement for fast and cheap improvements of user interfaces and has invented several usability methods, including heuristic evaluation.
Jakob found that by using established interaction patterns and methods enabled users to feel familiar and more comfortable. Along with making things more understood and so easier to use. Meaning that users could focus on what they needed to do instead of how to do it.
The average person can only keep 7 (plus or minus 2) items in their working memory.
Miller’s Law highlights the limitation on human’s ability to hold and make sense of information within their working memory.
In 1956, George Miller found that the immediate memory and judgment were both limited to around 7 pieces of information.
The human mind can remember about 7 bits of information when completing a task. This puts a limit on how many things a person is able to do at the same time. These aren’t just reserved for new pieces of information though, as you might be moving, thinking or remembering previous bits of information. A way to simplify information is to chunk it up, to make it more accessible and easier to think about by reducing the amount, into bitesize chunks.
Any task will inflate until all of the available time is spent.
Parkinson’s Law is based on the theory that work expands so as to fill the time available for its completion.
Cyril Northcote Parkinson in 1955 wrote about the law in the Economist after observing how the number of employees at the Colonial Office increased, while the British Empire declined even after the Colonial Office was folded into the Foreign Office.
Parkinson found that the officials were making work for each and the amount of time that the officials were given to perform a task was the amount of time it will take to complete the task. He observed officials elongating the task either by increasing the quality of work, the alternatives looked at in order to truly exhaust a task, as there were not defined goals or exit criteria.
Be liberal in what you accept, and conservative in what you send.
Postel’s Law is all about being forgiving of the user and the information formats that the user wants to use.
Postel’s Law (also known as the Robustness Principle) was formulated by Jon Postel, an early pioneer of the Internet. The Law is a design guideline for software, specifically in regards to TCP and networks.
Postel’s Law is all about being forgiving of the format in which information or data is given and where possible interpret it into the desired input that you’re expecting to avoid an error or the user having to find a different format. From the simple input type all the way through to uploading data types. It’s about reducing the error rate and making some as flexible as it is realistic too.
Tesler’s Law, also known as The Law of Conservation of Complexity, states that for any system there is a certain amount of complexity which cannot be reduced.
Tesla’s Law is based on the theory that work expands so as to fill the time available for its completion.
While working for Xerox in the mid-1980s, Larry Tesler realised that the way users interact with applications was just as important as the application itself. The book Designing for Interaction by Dan Saffer, includes an interview with Larry Tesler that describes the law of conservation of complexity.
Larry Tesler argues that, in most cases, an engineer should spend an extra week reducing the complexity of an application versus making millions of users spend an extra minute using the program because of the extra complexity.
Bruce Tognazzini found that people resist reductions to the amount of complexity in their lives. Thus, when an application is simplified, users begin attempting more complex tasks.
We’d all like to simplify processes and make them faster, but we have to take into account that sometimes there are things that cannot be simplified. In these cases, we’re simply transferring the complexity from one place to another.
If you’re interested in these laws, be sure to check out:
Laws of UX
Laws of UX is a collection of the maxims and principles that designers can consider when building user interfaces.
Next up, I’m just going to circle back to lean roadmaps, which I explored after looking at what you should own as a product person. This is quite topical within the teams I’m working in at the moment and has been mentioned a few times amongst different levels within the organisation.
So I’m going to take a step back to look at how User Experience is … defining a good product roadmap! Hopefully I can offer up some information and advice to the design community, but also help teams with in my own organisation.
Originally written as part of the ‘User Experience is …’ series for UX Collective.