The ‘Hierarchy of Design’ concept put forward by Lidwell, Holden and Butler in their 2003 book
In the 1940s Abraham Maslow published a psychology paper called
According to this theory, people generally seek to address the lowest of their needs before trying to attend to those on higher levels. When a lower level of need fulfillment is not in place, any fulfillment gained on a higher level is deemed unstable. When a person has no food, hunger is eventually going to overwhelm them. Then they will stop whatever they are doing and devote all their time and energy to satisfy their hunger instead.
In their book
Good designs, it is claimed, attend to the lower levels of the hierarchy before attempting to meet the needs of the higher levels.
“... a design must serve the low-level needs (e.g., it must function), before the higher-level needs, such as creativity, can begin to be addressed.”
Lidwell et al. have proposed the following five-levels for this hierarchy:
Products that exhibit only lower-level characteristics are deemed to be of no or low value, while those with higher-level characteristics are assumed to be of high value. As products exhibit higher-level characteristics so their value is deemed to increase.
A large number of articles, talks and blog posts have picked up on the idea of a design hierarchy. The simple order it leads to appeals to practitioners and inspired many to reproduce, refine and extend the ‘design hierarchy of needs’. A web search reveals a plethora of articles depicting altered versions of this pyramid with a variety of extensions and amendments.
The concept has, arguably, found its way into what one might view to be a generally accepted body of design knowledge and hence seems worth a critical review. Since the idea of the ‘design hierarchy of needs’ stems from Maslow’s theory, it seems worthwhile to first investigate how scholars assess Maslow’s original hierarchy of needs.
One of the main general criticisms of Maslow’s theory is that human needs are too complex to be reduced to a simple hierarchy. The representation of human needs in this manner has been called
It has more specifically been highlighted that the order of items in the hierarchy
The design hierarchy concept put forward by Lidwell et al. consists of a brief description on a single page in their encyclopedia ‘Universal Principles of Design’ and is hardly detailed or descriptive enough to amount to a theory comparable to Maslow’s. However, the authors explicitly state that the concept relies on Maslow's work and it thus seems reasonable to make general inferences and draw parallels regarding the details of the design hierarchy concept as well as the criticisms thereof.
The first question to ask is whether the categories proposed by Lidwell et al. are appropriate measures to determine a design’s success. On the face of it, there seems to be some validity to the bottom layers of the hierarchy. After all, every product needs some functionality that can be used and that performs its functions as expected. Functionality, Reliability and Usability hence seem necessary characteristics for any design.
Higher-level needs, such as Proficiency and Creativity are more questionable measures. A cheaper, but less reliable version of a product, for example, or a more environmentally-friendly, but less robust version might allow people to become more creative with a product precisely because of these characteristics. So, a customized set of characteristics might be more appropriate than the universal set proposed as some characteristics are more relevant in specific contexts than others.
One of the main claims put forward by Lidwell et al. is that their design hierarchy is to be interpreted as rigid and strict and that lower-level design needs must be completely fulfilled before higher ones can ‘begin to’ be addressed. In the context of the design hierarchy, this claim asserts that without functionality that satisfies the product purpose, the product cannot be assumed to ever be reliable, without complete reliability, there can be no usability and without 100% usability, there can be no proficiency and so on.
Firstly, it is difficult to assess when a lower-level need has been sufficiently addressed and a design can move on to the next level. What does it mean for a complex design, such as a car, for example, to satisfy the product purpose? Is it enough for it to transport people from one place to another? What about safety, entertainment, comfort and all the other design aspects that make a car well-designed? When is a car sufficiently reliable? What does complete usability look like and to whom should it apply? There are no obvious or easy answers to any of these questions and many of them also vary depending on the purpose and target users of any particular design.
Secondly, it is also possible for designs to exhibit these characteristics to varying levels. It is also not uncommon in complex designs to find some well-designed elements and some badly designed ones. Nobody would expect a space rocket to be easy to use, but it allows us to put satellites into space that undoubtedly improve our lives in many ways. Similarly, cars have a high proficiency, but are not that easy to operate. Some people take many years to become competent drivers, others never quite seem to make it. Some consumers are enthusiastically using Tesla's “Full Self-Driving” mode, but not always without crashing. While the utility of such a feature is undoubtedly significant, the technology often performs inconsistently, thereby making it sometimes unreliable. Similarly, a design might be very difficult to use or always function reliably, but provide a high level of proficiency at the same time.
Lidwell et al. also claim that designs gain in value as they satisfy various levels of the hierarchy. So, designs that satisfy the Functionality and Reliability levels, but none of the higher ones have some value. While people who satisfy only the lowest level of Maslow’s hierarchy, like air, nourishment, sex and sleep are undoubtedly still humans, it is difficult to defend this view for products.
In practice, designs only gain value when they fulfill, to some degree, all three base levels of functionality, reliability and usability. Something can only be called a design when it has useful functions, performs those reasonably reliably and is also usable.
If any of those characteristics are missing, it is an idea, but not a design. The depiction of these characteristics in terms of a hierarchy is hence flawed and misleading due to the implication of a sequential relationship between the levels.
Furthermore, the value of any design is defined by the observer and the market and is not inherent in the design itself. How we determine the value of a product is not universal and can vary depending on circumstance, interest, culture or age. A surfboard is only useful to someone who likes surfing, a cross might only have value to a christian and acne cream is rarely useful to old people. Value is not universal and is defined differently in varying contexts, regardless of functionality, reliability, usability and so on.
While the design hierarchy concept recognises that certain characteristics of designs are dependent on others, it is inherently flawed in so far as it represents a strict succession of specific characteristics. The relationship between design characteristics is interdependent, rather than hierarchical and one characteristic cannot be designed separately from other, related ones.
Any characteristic may exist in any design to a varying degree, and for some designs specific characteristics are more relevant than others. A universal set of characteristics is unlikely to be appropriate for all designs. The context of use and the users may determine the characteristics necessary to make a design good.
It is also not a function of the creator to assess when a design has the necessary characteristics to make it good or valuable as the definition of these characteristics is a function of the user. A more accurate definition of characteristics that make designs good cannot focus on the design alone and must take the user into account.
The simplicity of the ‘Hierarchy of Design’ concept is appealing, but it is not very helpful in assessing the value of a design. Designers should stop using the design hierarchy concept and find a more flexible, less hierarchical way to evaluate designs.
Universal Principles of Design
Motivation and Personality
A Theory of User Delight: Why Usability Is the Foundation for Delightful Experiences
Maslow's hierarchy of needs
A Theory of Human Motivation
There is no such thing as UX Design
Needs Before Wants in User Experiences – Maslow and the Hierarchy of Needs
Designing For A Hierarchy Of Needs
Gratification, Metamotivation, and Maslow, K. G. Agrawal and B. R. Sharma, Vikalpa, Vol. 2, No. 4, October 1977
Praise & Criticism: Hierarchy of Needs
The Cultural Relativity of the Quality of Life Concept
Cooke, Bill, Mills, A. J., and Kelley, Elizabeth S. (2005) “Situating Maslow in Cold War America. A Recontextualization of Management Theory”, Group & Organization Management, 30 (2), pp.129-152.
Needs and Subjective Well-Being Around the World
Evaluating the applicability of Maslow's theory of motivation to ancillary staff
Psychology of Web Design
Challenging Maslow’s Hierarchy of Needs
Maslow’s “Hierarchy of Needs”: A Critique
Maslow’s Hierarchy: Separating Fact From Fiction
The Failure of Self-Actualization Theory: A Critique of Carl Rogers and Abraham Maslow
Usability 101: Introduction to Usability