The O.G. guide to human-centered design from the Godfather of Design himself, Don Norman.

In the design process, what we think of as common sense often is overlooked. Norman emphasizes the importance of human-centered design, and how we should focus and build around the intuitive interaction between the things we design and the people who use them. Great design doesn’t exist in a bubble. It must account for human behavior and our pesky cognitive limitations, and beyond function, products and processes should be enjoyable.

The Design of Everyday Things in 10 passages:

1.  There’s no such thing as user error.

We have a nasty tendency to blame ourselves when we can’t figure out a new technology, but our failure to understand a product intuitively is almost always a clue of poor design. When you can’t quite figure out how to use something, you’re certainly not the only one. 

2.  If it is difficult or impossible for humans to use, it is useless.

It doesn’t matter how revolutionary a technology is if it cannot be practically applied to peoples’ lives. This is easy to forget in this era of technology hyperdrive, as it becomes really easy to add fringe features and make things too complicated. 

3.  A well-designed product or process teaches its users how to use it.

We rarely read user manuals, and reading them often leaves us more confused than when we started. Good design allows you to learn as you go, based on signals and clues built into the product or process. 

Affordances are the potential actions or possibilities that an object or interface inherently allows. A chair affords sitting. A button affords pressing. A slider affords dragging. These help users understand what actions are possible without explicit instructions, based on physical characteristics or learned conventions.  

Signifiers are sensory cues (visual, auditory, tactile) that communicate how to use an interface, making affordances more obvious. These include icons (magnifying glass for search), colors to group elements, text, sounds, shapes and patterns (a raised button invites pressing), etc.

Affordances define what actions are possible, and signifiers help us discover and understand those possibilities. A door handle (affordance) might be shaped or labeled (signifier) to indicate whether to push or pull, for example.  

4.  Understanding human psychology is essential to good design.

We engage with products on 3 different psychological levels:

  • Visceral: unconsciously without thinking (like how we breathe or digest)
  • Behavioral: instinctive, reflexive responses (like pulling our hand from a fire)
  • Reflective: conscious, higher-level experience (like planning or problem-solving).

To design processes and products effectively, we need to consider and address all 3. 

5.  Fixing bad design requires a thoughtful exploration into the root cause.

We often rush to solve problems, but it would serve us well to take our time to really nail the root cause before rushing into solutions. By repeatedly asking “why?” we can identify more subtle errors that may be the actual cause of the more obvious ones, allowing us to properly identify the most effective solution.

6.  Good design uses constraint. 

Constraints are an educational tool that helps people understand how to use a product. IKEA furniture uses nuts and bolts of various sizes that only fit into one place, making it easier to put together. And regardless of where we are from, we are influenced by the international screw standard (“lefty loosy, righty tighty”), making it easier for everyone to use a screwdriver. 

7.  Great products/processes communicate with users through feedback. 

When we set our phone alarm we will usually get some kind of indicator–a ‘bell’ icon for example–that it is set. Good design should always inform us of the status (e.g. whether an alarm system is on when we leave home). 

8.  Human-centered design requires 4 steps.

  1. Study: We can only understand a design’s problem by observing people interacting with it.
  2. Ideate: We should restrain from ideating until we’ve clearly defined our design problem with confidence, and then let the creativity flow.
  3. Prototype: The solutions we develop should solve our design problem, ideally without creating new problems. 
  4. Test: We can only confirm #3 through testing and iteration.

9.  Great design alone doesn’t make a great product. 

Touchscreens have been possible on phones since the 1980s, but only gained adoption in the early 2000s. Why? Before then, there simply wasn’t incentive alignment between marketers (with business objectives) and designers. Screens were far too expensive to scale effectively, so designers were forced to build less expensive, harder-to-use products. This equation only changed when touchscreen technology became cheaper.

10.  Patience is critical to good design.

Norman’s Law: the day product development starts, it’s already over budget and behind schedule. You have to expect setbacks and even build them into your design process to realistically plan production. 

How I’ll Apply It

This was the first design book I ever read, but I wanted to summarize it again because it is truly timeless and still foundational today. The biggest takeaway for me was in recognizing how easily we can get so caught up in our day-to-day world and work that we can lose perspective of the fact that something obvious to us may not be obvious or intuitive to others. Our users generally just don’t care as much about any particular product as that product’s creator, and that reminder helps ground us and keep us focused on the context of our user’s actual experience.