The Design of Everyday Things (39 page)

Solving the Correct Problem

Engineers and businesspeople are trained to solve problems. Designers are trained to discover the real problems. A brilliant solution to the wrong problem can be worse than no solution at all: solve the correct problem.

Good designers never start by trying to solve the problem given to them: they start by trying to understand what the real issues are. As a result, rather than converge upon a solution, they diverge, studying people and what they are trying to accomplish, generating idea after idea after idea. It drives managers crazy. Managers want to see progress: designers seem to be going backward when they are given a precise problem and instead of getting to work, they ignore it and generate new issues to consider, new directions to explore. And not just one, but many. What is going on?

The key emphasis of this book is the importance of developing products that fit the needs and capabilities of people. Design can be driven by many different concerns. Sometimes it is driven by technology, sometimes by competitive pressures or by aesthetics. Some designs explore the limits of technological possibilities; some explore the range of imagination, of society, of art or fashion. Engineering design tends to emphasize reliability, cost, and efficiency. The focus of this book, and of the discipline called human-centered design, is to ensure that the result fits human desires, needs, and capabilities. After all, why do we make products? We make them for people to use.

Designers have developed a number of techniques to avoid being captured by too facile a solution. They take the original problem
as a suggestion, not as a final statement, then think broadly about what the issues underlying this problem statement might really be (as was done through the “Five Whys” approach to getting at the root cause, described in
Chapter 5
). Most important of all is that the process be iterative and expansive. Designers resist the temptation to jump immediately to a solution for the stated problem. Instead, they first spend time determining what basic, fundamental (root) issue needs to be addressed. They don't try to search for a solution until they have determined the real problem, and even then, instead of solving that problem, they stop to consider a wide range of potential solutions. Only then will they finally converge upon their proposal. This process is called
design thinking
.

Design thinking is not an exclusive property of designers—all great innovators have practiced this, even if unknowingly, regardless of whether they were artists or poets, writers or scientists, engineers or businesspeople. But because designers pride themselves on their ability to innovate, to find creative solutions to fundamental problems, design thinking has become the hallmark of the modern design firm. Two of the powerful tools of design thinking are human-centered design and the double-diamond diverge-converge model of design.

Human-centered design (HCD) is the process of ensuring that people's needs are met, that the resulting product is understandable and usable, that it accomplishes the desired tasks, and that the experience of use is positive and enjoyable. Effective design needs to satisfy a large number of constraints and concerns, including shape and form, cost and efficiency, reliability and effectiveness, understandability and usability, the pleasure of the appearance, the pride of ownership, and the joy of actual use. HCD is a procedure for addressing these requirements, but with an emphasis on two things: solving the right problem, and doing so in a way that meets human needs and capabilities.

Over time, the many different people and industries that have been involved in design have settled upon a common set of methods for doing HCD. Everyone has his or her own favorite method,
but all are variants on the common theme: iterate through the four stages of observation, generation, prototyping, and testing. But even before this, there is one overriding principle: solve the right problem.

These two components of design—finding the right problem and meeting human needs and capabilities—give rise to two phases of the design process. The first phase is to find the right problem, the second is to find the right solution. Both phases use the HCD process. This double-phase approach to design led the British Design Council to describe it as a “double diamond.” So that is where we start the story.

The Double-Diamond Model of Design

FIGURE 6.1.
   
The Double-Diamond Model of Design.
Start with an idea, and through the initial design research, expand the thinking to explore the fundamental issues. Only then is it time to converge upon the real, underlying problem. Similarly, use design research tools to explore a wide variety of solutions before converging upon one. (Slightly modified from the work of the British Design Council, 2005.)

Designers often start by questioning the problem given to them: they expand the scope of the problem, diverging to examine all the fundamental issues that underlie it. Then they converge upon a single problem statement. During the solution phase of their studies, they first expand the space of possible solutions, the divergence phase. Finally, they converge upon a proposed solution (
Figure 6.1
). This
double diverge-converge pattern was first introduced in 2005 by the British Design Council, which called it the
double-diamond design process model
. The Design Council divided the design process into four stages: “discover” and “define”—for the divergence and convergence phases of finding the right problem,
and “develop” and “deliver”—for the divergence and convergence phases of finding the right solution.

The double diverge-converge process is quite effective at freeing designers from unnecessary restrictions to the problem and solution spaces. But you can sympathize with a product manager who, having given the designers a problem to solve, finds them questioning the assignment and insisting on traveling all over the world to seek deeper understanding. Even when the designers start focusing upon the problem, they do not seem to make progress, but instead develop a wide variety of ideas and thoughts, many only half-formed, many clearly impractical. All this can be rather unsettling to the product manager who, concerned about meeting the schedule, wants to see immediate convergence. To add to the frustration of the product manager, as the designers start to converge upon a solution, they may realize that they have inappropriately formulated the problem, so the entire process must be repeated (although it can go more quickly this time).

This repeated divergence and convergence is important in properly determining the right problem to be solved and then the best way to solve it. It looks chaotic and ill-structured, but it actually follows well-established principles and procedures. How does the product manager keep the entire team on schedule despite the apparent random and divergent methods of designers? Encourage their free exploration, but hold them to the schedule (and budget) constraints. There is nothing like a firm deadline to get creative minds to reach convergence.

The Human-Centered Design Process

The double-diamond describes the two phases of design: finding the right problem and fulfilling human needs. But how are these actually done? This is where the human-centered design process comes into play: it takes place within the double-diamond diverge-converge process.

There are four different activities in the human-centered design process (
Figure 6.2
):

FIGURE 6.2.
   
The Iterative Cycle of Human-Centered Design.
Make observations on the intended target population, generate ideas, produce prototypes and test them. Repeat until satisfied. This is often called the
spiral method
(rather than the circle depicted here), to emphasize that each iteration through the stages makes progress.

       
1.
   
Observation

       
2.
   
Idea generation (ideation)

       
3.
   
Prototyping

       
4.
   
Testing

These four activities are iterated; that is, they are repeated over and over, with each cycle yielding more insights and getting closer to the desired solution. Now let us examine each activity separately.

OBSERVATION

The initial research to understand the nature of the problem itself is part of the discipline of design research. Note that this is research about the customer and the people who will use the products under consideration. It is not the kind of research that scientists do in their laboratories, trying to find new laws of nature. The design researcher will go to the potential customers, observing their activities, attempting to understand their interests, motives, and true needs. The problem definition for the product design will come from this deep understanding of the goals the people are trying to accomplish and the impediments they experience. One of its most critical techniques is to observe the would-be customers in their natural environment, in their normal lives, wherever the product or service being designed will actually be used. Watch them in their homes, schools, and offices. Watch them commute, at parties, at mealtime, and with friends at the local bar. Follow them into the shower if necessary, because it is essential to understand the real situations that they encounter, not some pure isolated experience. This technique is called
applied ethnography
, a method adapted from the field of anthropology. Applied ethnography differs from the slower, more methodical, research-oriented practice of academic anthropologists because the goals are different.
For one, design researchers have the goal of determining human needs that can be addressed through new products. For another, product cycles are driven by schedule and budget, both of which require more rapid assessment than is typical in academic studies that might go on for years.

It's important that the people being observed match those of the intended audience. Note that traditional measures of people, such as age, education, and income, are not always important: what matters most are the activities to be performed. Even when we look at widely different cultures, the activities are often surprisingly similar. As a result, the studies can focus upon the activities and how they get done, while being sensitive to how the local environment and culture might modify those activities. In some cases, such as the products widely used in business, the activity dominates. Thus, automobiles, computers, and phones are pretty standardized across the world because their designs reflect the activities being supported.

In some cases, detailed analyses of the intended group are necessary. Japanese teenage girls are quite different from Japanese women, and in turn, very different from German teenage girls. If a product is intended for subcultures like these, the exact population must be studied. Another way of putting it is that different products serve different needs. Some products are also symbols of status or group membership. Here, although they perform useful functions, they are also fashion statements. This is where teenagers in one culture differ from those of another, and even from younger children and older adults of the same culture. Design researchers must carefully adjust the focus of their observations to the intended market and people for whom the product is intended.

Will the product be used in some country other than where it is being designed? There is only one way to find out: go there (and always include natives in the team). Don't take a shortcut and stay home, talking to students or visitors from that country while remaining in your own: what you will learn is seldom an accurate reflection of the target population or of the ways in which the proposed product will actually be used. There is no substitute for
direct observation of and interaction with the people who will be using the product.