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The Design of Everyday Things

Tags: #design #psychology #technology #user experience #usability

Authors: Don Norman

Overview

In this book, I aim to equip readers with a starter kit for good design. It’s intended to be a valuable resource for anyone: everyday people navigating a world filled with complex technology, designers striving to create user-friendly products, and even those who simply want to understand why the world seems so full of frustrating, poorly designed things. This book is about human-centered design (HCD), a philosophy that prioritizes people’s needs, capabilities, and behavior when designing products and systems. The core of my argument is that the difficulties people experience with everyday things are almost always the fault of bad design, not the fault of the user. I guide readers through the fundamental principles of HCD, grounded in the psychology of human action and cognition. I explore concepts like affordances, signifiers, constraints, mappings, feedback, and the crucial role of conceptual models in shaping a user’s understanding and experience. You’ll learn how these principles can be applied to solve design problems and create pleasurable, satisfying user experiences. Beyond theoretical principles, I delve into the realities of designing in the business world. You’ll see how the pressure of competition, tight budgets, and demanding schedules often lead to compromises that undermine good design, and I’ll offer strategies to navigate these challenges. Finally, I explore the impact of new technologies on design, arguing for a focus on designing for activities rather than specific individuals to create truly universal designs. This book is a call to action for all of us—designers and users alike. It encourages us to observe the world with a critical eye, to advocate for usable, understandable products, and to appreciate the power of good design to enhance our lives. As you read, I hope you’ll not only become more aware of the world around you but also become an advocate for good design.

Book Outline

1. The Psychopathology of Everyday Things

This chapter introduces the fundamental problem addressed by the book: the difficulties people have in using everyday objects, blaming themselves when the fault lies in the design. Two concepts are introduced: discoverability and understanding, along with an explanation of why so many products are difficult to use and understand.

Key concept: Discoverability and Understanding: Two of the most important characteristics of good design are discoverability and understanding. Discoverability asks: Is it possible to even figure out what actions are possible and where and how to perform them? Understanding asks: What does it all mean? How is the product supposed to be used? What do all the different controls and settings mean?

2. The Psychology of Everyday Actions

This chapter introduces a simple model of human action called the Seven Stages of Action, demonstrating its applicability to understanding how people interact with the world. It examines the interplay of cognition, emotion, and behavior. It shows how good design can make all the difference to successful product use.

Key concept: Seven Stages of Action: 1. Goal (form the goal), 2. Plan (the action), 3. Specify (an action sequence), 4. Perform (the action sequence), 5. Perceive (the state of the world), 6. Interpret (the perception), 7. Compare (the outcome with the goal)

3. Knowledge in the Head and in the World

This chapter shows how knowledge in the world combines with knowledge in the head to produce behavior. It explores the nature of human memory, reminding the reader that memory is knowledge in the head and providing a simple framework for understanding the two major components of memory: short-term or working memory, and long-term memory. It concludes with a discussion of the important design principle called natural mapping.

Key concept: Precise Behavior from Imprecise Knowledge: Precise behavior can emerge from imprecise knowledge for four reasons: 1. Knowledge is both in the head and in the world. 2. Great precision is not required. 3. Natural constraints exist in the world. 4. Knowledge of cultural constraints and conventions exists in the head.

4. Knowing What to Do: Constraints, Discoverability, and Feedback

This chapter explores the role of constraints in simplifying what must be kept in memory, and how they can provide powerful clues as to how things should be used and interpreted. It introduces the four major types of constraints: physical, cultural, semantic, and logical. It explores the power of forcing functions, specialized forms of physical constraints that can prevent inappropriate behavior.

Key concept: Four Kinds of Constraints: Physical, Cultural, Semantic, and Logical: * Physical constraints rely upon properties of the physical world for their operation: no special training is necessary. * Cultural constraints rely upon accepted cultural conventions. * Semantic constraints rely upon the meaning of the situation to control the set of possible actions. * Logical constraints exploit the logical relationships between the spatial or functional layout of components and the things that they affect or are affected by.

5. Human Error? No, Bad Design

This chapter explores the nature of human error, showing how accidents often have numerous contributing causes, no single one of which is the root cause of the incident. The chapter examines the nature of human error and presents a classification scheme. It introduces the distinction between slips, which result from an error in execution, and mistakes, which result from an error in planning or goal setting. It shows how both slips and mistakes can be reduced through design.

Key concept: Two Types of Errors: Slips and Mistakes: Slips result from automatic behavior, when subconscious actions that are intended to satisfy our goals get waylaid en route. Mistakes result from conscious deliberations.

6. Design Thinking

This chapter explores the design process, starting with the need to determine what the real problem is, a frequent difficulty in product development because it is so easy to focus on an apparent problem rather than the true, underlying one. It introduces the two phases of the design process: finding the right problem and fulfilling human needs. It discusses the human-centered design process and the double-diamond model of design. It shows why the design process must be iterative and how to manage the inherent conflict between design and engineering.

Key concept: Don Norman’s Law of Product Development: The day a product development process starts, it is behind schedule and above budget.

7. Design in the World of Business

This chapter explores the challenges of design in the real world of business, with a focus on the interplay between the needs of people and the pressures of business. It discusses the phenomenon called ‘featuritis,’ driven by the competitive need to continually add new features to products, while seldom removing unneeded older ones. It examines the interplay between new technologies and design, between incremental and radical innovation, and concludes with discussion of the social and moral obligations of designers.

Key concept: Two Forms of Innovation: Incremental and Radical: Incremental innovation starts with existing products and makes them better. Radical innovation starts fresh, often driven by new technologies that make possible new capabilities.

Essential Questions

1. Why are so many everyday objects difficult to use, and whose fault is it?

The central problem is that many everyday objects are difficult to use and understand. The book posits that this is due to bad design rather than user incompetence. Norman introduces the concepts of discoverability (figuring out possible actions) and understanding (interpreting the product’s meaning and use). He supports his argument with numerous real-world examples of confusing designs, emphasizing the need for designers to understand human psychology and apply principles of good design to bridge the gap between user intention and product functionality.

2. How do people interact with objects, and what are the key stages involved in this process?

The Seven Stages of Action model provides a framework for understanding how people interact with the world. It breaks down human action into a cyclical process: forming a goal, planning, specifying actions, performing them, perceiving the outcome, interpreting it, and comparing it to the initial goal. This model highlights the importance of feedback and conceptual models in design. By understanding these stages, designers can create products that guide users seamlessly through the interaction process, minimizing errors and frustration.

3. How do humans manage to function effectively in a world full of complex information and objects, despite our limited memory capacity?

Humans compensate for their imperfect memory by relying on both knowledge in the head (internal memory) and knowledge in the world (external cues and constraints). Great precision is not always required, and natural and cultural constraints help narrow down possible actions, simplifying decision-making. This highlights the importance of designing products that leverage external cues like signifiers, affordances, and natural mappings to reduce cognitive load and guide user behavior.

4. What are the different types of human error, and how do they affect our interactions with technology?

Errors can be broadly classified as slips (errors in execution) and mistakes (errors in planning or goal setting). Slips often result from automatic behavior and are more common in skilled individuals. Mistakes result from conscious deliberations and are more common in novices. Understanding the different types of errors and their causes is crucial for designing systems that anticipate and mitigate human fallibility.

5. What is human-centered design, and how does it differ from traditional design approaches?

Human-centered design is an iterative, user-focused approach that emphasizes understanding user needs and iterating on designs based on feedback. It involves four key activities: observation, idea generation, prototyping, and testing. This process helps ensure that products truly meet user needs and are easy to use and understand.

Key Takeaways

1. Conceptual models are crucial for understanding and usability.

Humans form mental models to understand how things work. These models can be inaccurate or incomplete, leading to errors. Good design provides a clear, accurate conceptual model that matches the user’s mental model, enabling understanding and control.

Practical Application:

In AI, designing a conversational agent, consider the user’s mental model of conversation. Provide clear feedback acknowledging the user’s input and indicating the system’s understanding. Use natural language and familiar conversational patterns to make interactions feel intuitive.

2. Design should anticipate and mitigate the impact of interruptions.

Interruptions are a major source of errors, especially memory lapses. When interrupted, users must remember their previous state, goal, and relevant information to resume effectively. Good design minimizes interruptions and supports smooth resumption of tasks.

Practical Application:

In AI-powered medical diagnosis systems, design for potential interruptions. Allow doctors to easily resume their analysis after being called away. Provide clear visual cues that highlight where they left off and summarize key findings, reducing cognitive load and minimizing potential errors.

3. The Paradox of Automation: Design for resilience, not just efficiency.

Automation can improve efficiency and safety, but its failures can be catastrophic. Designers must understand the limitations of automation and design for situations where it fails. Resilience engineering aims to create systems that adapt and respond to unexpected events, even when automation breaks down.

Practical Application:

When designing a self-driving car, avoid relying solely on assumptions about human behavior. Conduct rigorous testing in realistic, complex environments to identify potential edge cases where the system might fail. Implement robust fallback mechanisms and driver-intervention protocols to mitigate risks.

Suggested Deep Dive

Chapter: Chapter 5: Human Error? No, Bad Design

Chapter 5’s exploration of human error, while insightful, could benefit from a deeper dive into the nuances of cognitive biases and the challenges of modeling human behavior in AI systems. This is especially relevant in the context of AI safety, where understanding and mitigating potential errors is crucial.

Memorable Quotes

Chapter 1: The Psychopathology of Everyday Things. 3

If I were placed in the cockpit of a modern jet airliner, my inability to perform well would neither surprise nor bother me. But why should I have trouble with doors and light switches, water faucets and stoves?

Chapter 1: The Psychopathology of Everyday Things. 30

The term affordance refers to the relationship between a physical object and a person … that determine just how the object could possibly be used.

Chapter 1: The Psychopathology of Everyday Things. 40

In design, signifiers are more important than affordances, for they communicate how to use the design.

Chapter 2: The Psychology of Everyday Actions. 65

People don’t want to buy a quarter-inch drill. They want a quarter-inch hole!

Chapter 5: Human Error? No, Bad Design. 208

Eliminate the term human error. Instead, talk about communication and interaction: what we call an error is usually bad communication or interaction.

Comparative Analysis

This book, a classic in the field of design and human-computer interaction, stands out for its clear, engaging style and its focus on the psychology of everyday actions. Unlike more technical texts, Norman makes complex concepts like affordances, signifiers, and mental models accessible to a wide audience. It shares common ground with other notable works in the field, such as About Face by Alan Cooper et al., which also emphasizes user-centered design principles. However, The Design of Everyday Things goes beyond usability and delves into the emotional impact of design, a theme explored more deeply in Norman’s later book, Emotional Design. Norman’s emphasis on the role of constraints and forcing functions in guiding user behavior is particularly relevant to the field of AI safety, where designing systems that anticipate and prevent human error is paramount.

Reflection

This book provides a timeless foundation for understanding human interaction with technology, a foundation that remains relevant in our increasingly AI-driven world. Norman’s core message that good design must prioritize human needs and capabilities is particularly critical as we develop increasingly complex, autonomous systems. However, the book’s focus on physical objects and everyday tasks can feel somewhat dated in a world dominated by digital interfaces and virtual interactions. While the principles remain applicable, their application to AI systems, with their unique challenges and possibilities, requires further exploration. Additionally, Norman’s somewhat simplistic view of human error, attributing it almost entirely to bad design, might overlook the inherent complexity of human cognition and the potential for unpredictable behavior. Despite these limitations, The Design of Everyday Things remains a seminal work in the field of design. It reminds us to put people at the center of our creations and to strive for designs that are not only functional but also enjoyable, understandable, and safe.

Flashcards

What is an affordance?

The relationship between the properties of an object and the capabilities of the agent that determine how the object could possibly be used. For example, a chair affords sitting.

What is a signifier?

Perceptible signals that communicate appropriate behavior to a person. For example, a sign that says “PUSH” on a door.

What is mapping in design?

The relationship between the elements of two sets of things. For example, the relationship between the layout of stovetop controls and the corresponding burners.

What is natural mapping?

Taking advantage of spatial analogies to create intuitive mappings. For example, to move an object up, the control should also move up.

What is feedback in design?

Communicating the results of an action to the user.

What is a conceptual model?

A simplified explanation of how something works, which helps users understand and predict the system’s behavior.

What is a slip?

Errors in executing a plan or sequence of actions. Often caused by inattention or distractions.

What is a mistake?

Errors in choosing the goal or plan. Often caused by misinterpreting the situation or applying the wrong rules.

What is human-centered design?

A design process that prioritizes user needs and involves iterating through observation, idea generation, prototyping, and testing.

What is resilience engineering?

Designing systems and procedures that can adapt and respond to unexpected events and failures.