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User Groups

One of the most important tasks of developing a design strategy is characterizing the groups of people who will interact/use it.

What are user groups?

A user is anyone who interacts with a designed intervention, or is directly or indirectly affected by its function.

Users can be defined according to the stages of a product's life cycle. Users from different user groups will perform different tasks with a product. Good design supports all those tasks, regardless of which group a user belongs.

How are user groups characterized?

In this section, we'll first consider how to identify and characterize user groups generally. Then we'll look more closely at the two times during our design process that we describe, refine, and verify user groups.

Identifying user groups

Users can be grouped broadly by how they use a design intervention; these categories also coincide with the stages of a product's life cycle.

Generally, every intervention has more or less the same user groups (especially from an engineering point of view):

End-users:
the people who buy and use the product.
Co-users:
people affected by the intervention without necessarily being a direct end-user.
Manufacturers & implementers:
people who manufacture the intervention or otherwise make your design “real”.
Maintenance workers:
people charged with maintaining products and fixing them when they break.
End-of-life users:
people involved in dealing with the product once it has finished being useful - recyclers, remanufacturers, etc.
Supply chain & distribution workers:
people involved with getting the products from the “factory” to the “store”.
Management:
people in charge of managing the design, manufacture, distribution, maintenance, and end of life of products.
Salespeople and marketers:
people concerned with making sure someone will want to buy (and, more importantly, use) the product.
Lawyers:
people who make sure everything that's done is done legally and fairly.

For instance, consider an automobile.

  • The end-users of the automobile are the people who will drive it.
  • Mechanics are users too, although their interactions with the automobile will be very different from those of the end-users. So we treat them as a separate user group.
  • Manufacturers and those directly involved in recycling the automobile at the end of its life also constitute distinct user groups based on the kinds of interactions they will likely have with the automobile.

People in each of these groups may well be characterized in very different ways: cognitive skill, physical abilities, income, training, social standing, etc. can all differ radically between user groups.

Also, each user group's characteristics will be different for different products - e.g., people who drive Rolls Royce cars are generally different from people who drive Toyota Yarises.

Very significantly, co-users are often forgotten or neglected during design. This is usually bad because they can significantly alter the situations involving the intervention.

  • For instance, passengers in a car, pedestrians, and wild animals crossing streets can all be thought of as co-users.
    • If a moose gets in front of your car as you're driving down the highway at night, things may turn out very badly - for you as well as the moose.
    • Accidents can happen when passengers distract a car's driver.
    • On the other hand, passengers can also help the driver navigate, or even make them aware of dangerous situations.
    • If you have to use a rickety ladder, it might be very helpful to have a co-user hold the ladder to help stabilize it - and you.

Notice that the potential direct impact of the intervention on each user group gets smaller as you go down the list of user groups. This is only because our interest is in the intervention from the engineering point of view; things would be different if we were considering this matter from some other point of view.

This list is not exhaustive. Depending on the nature of the design imbalance you are trying to resolve with your design, some of these user groups can be safely ignored, and other groups (e.g., “installers” of equipment) will have to be added. You will have to think this through yourself for each design project.

Characterizing each user group

Once you've identified all the main user groups, you now have to decide what types of people will be included in each group.

Remember that you can't design something that literally anyone can use, or make, or sell, or recycle. Each user group will exclude some individuals. The question is: which individuals should you or must you exclude? The answer will depend on the situation you're trying to address, and the product strategy that you take in your design.

To characterize each user group, you simply list relevant characteristics of the kinds of people you want to include.

  • A simple point-form list is enough.
  • Ideally, this list will be exhaustive, but this will rarely happen in practice.
  • Make sure you're covering the most essential characteristics that are relevant to the situation you're trying to address.

Consider building a deck on your house. Do you need to include a wheelchair ramp in your design? If you don't, then anyone who uses a wheelchair will probably be excluded from using your deck. To decide, you need to consider the actual situation.

  • If no one in your household and no one likely to visit you uses a wheelchair, then you don't need to add one.

Consider renovating the entrance to a public museum. Do you need a wheelchair ramp in your design? Why? What makes this case different?

Consider these two strategic cases.

  • In one case, you are trying to design a new intervention that will only significantly lower purchase price (i.e., a “low innovation” type of strategy), thereby making that intervention economically available to more people, and so improving general well-being.
  • In the other case, you are developing an entirely new intervention (i.e., a “high innovation” strategy) specifically intended to improve the general well-being of user groups who had theretofore been neglected by existing interventions; like most substantially new interventions, purchase prices will probably be high.
  • Who is being excluded or included in each case? Why? Is that really the best thing to do?

Exercise for the reader:

Consider the two strategic cases above. How will the difference in strategy affect descriptions of all the different user groups? Try to be as specific as possible.

What are good characteristics?

It's important to choose the characteristics that most matter to the specific design situation. Some characteristics are better than others. It's informative to consider some typical beginner's mistakes to help identify what constitutes good characteristics.

Case 1: designing a human-powered vehicle for urban settings

  • The mistake: “We'll design it for use in Toronto.”
  • What does it mean for a vehicle to be for Toronto?
  • The characteristics are those that describe Toronto. Things like:
    • variation in climate (hours of daylight, temperatures, amounts and types of precipitation, etc.),
    • sizes, number, and quality of roads,
    • alignment of the roads (if the sun is in your eyes….),
    • existence (or lack) of cycling lanes,
    • cultures and nationalities present,
    • rates or minor theft, muggings, and similar crimes,
    • vertical changes in geography (Toronto is not like, say, San Francisco),
    • insurance rates (if any) for human-powered urban vehicles,
    • and so on.
  • Notice that the characteristics in the list are easily related to using a human-powered vehicle.
    • How tall the buildings are, who the city mascot is, or whether the city is in the north or south hemisphere probably have little if anything to do with this design situation.
  • The key insight is that if you describe Toronto by the truly useful characteristics, you will realize there are many other places where you can probably market your vehicle. This is good.

Case 2: designing an office chair

  • The mistake: “We'll design it for women.”
  • What exactly does that mean?
    • Women are on average shorter and lighter than men. But does that mean that short or thin men cannot use the office chair?
  • Characteristics that pertain in this case might include:
    • weight and height,
    • loose clothing (e.g., women wearing long skirts, but also men from certain cultures),
    • physical strength (to work the chair controls),
    • range of key dimensions (e.g., lengths of forearms, lower legs, etc.),
    • and so on.
  • Again, notice that by determining the correct characteristics, one is driven to develop a broader potential market - which also means more people will stand to benefit from you design.
  • Notice how the characteristics could apply to a number of different user groups too.

Example 1: End user of for domestic electric kettle

User group: End user

  • Cognitively able to perform simple and frequent household tasks.
  • Sufficiently dexterous and strong to carry/move 1.5 kg for 2 minutes.
  • Able to afford $10/yr amortized purchase price.
  • Has ready access to sources of electricity and/or stove.

Exercise for the reader:

  1. Is the user group above defined as you would have expected? Why (or why not)? What is different between the example as given and how you would have described the end user? Is there anything important missing? Are you surprised that age is not considered? Why (or why not)?
  2. Why is age not specified?
  3. How do you think the weight of 1.5 kg was arrived at?
  4. With respect to kettle design, why do you think it's important to specify the availability of both heat and electricity?
  5. Why do you think the purchase price is described as an annual cost?
  6. Consider a typical end user of a kettle. Consider setting a target of lessening the cognitive load on that user, even if no existing user has complained about the complexity of the kettle. If you achieve that target, what happens to the potential size of the end-user group (all else being equal)? How might one generalize this effect to a design principle?

Example 2: Manufacturing worker for automotive manufacturer

User group: Manufacturer

  • Cognitively able to perform moderately complex tasks in moderately hazardous environments.
  • Sufficiently strong to carry/move 20 kg for 5 minutes.
  • Eyesight (with or without aids) able to see down to 8-point fonts within 1.5m.
  • Hearing (with or without aids) able to pass HINT (or comparable) test.
  • Able to work up to 8 hrs/day, with breaks.
  • Has minimum high-school education, including facility in the local language.

Initial user groups

The first time we consider user groups is after a situation scan. At this point, we're still trying to understand the current situation - the way things are - for the sake of understanding the context into which we'll be adding our designed interventions.

At this point of the design process, we have researched existing products, designs, and solutions. Those existing interventions were designed for specific user groups. Your job here is to try to describe the user groups by inferring their characteristics from information about the interventions themselves.

For instance, consider a Toyota Yaris and a Rolls Royce Silver Shadow. What can you infer about the various user groups just based on what you can learn about the cars themselves? Clearly, the owners of the Rolls will have more disposable income than the Yaris owners. But what else can you tell about them? What features of the car itself might tell you something about the owners? Are they young or old? Are they able-bodied or not? What level of education might you expect them to have? These are all things you can intuit - and in many cases actually find out about via the Web - and that will tell you about the kinds of users each car was designed for.

Exercise for the reader:

Consider the maintenance user group of Rolls vs Yaris. What do you think the differences are between “mechanics” of the two cars? Once you have written down some ideas, use the Great and Powerful Google to find out the actual differences. You may well be surprised.

Use your background research to intuit the characteristics of each of the user groups for your project. Document those characteristics by referring to pertinent background research. At this point, you are just describing to the best of your ability the actual user groups for existing interventions. You are not deciding whether those user groups are particularly exclusionary or otherwise problematic. You're just reporting on what you've learned about existing designs.

Revising user group descriptions

Further into the design process - when you're defining the expectations you'll put on your own design to improve the current state of affairs - you have a chance to tweak the user group descriptions to align better with what you want to achieve with your own design.

To do this, you must have already documented some systemic flaws in existing interventions. Based on thinking about those flaws, you should be able to either (a) verify that the user group descriptions are still reasonable or (b) determine specific changes that will “improve” the user groups. Here are some examples.

Example: neglecting a significant group of disabled users. It may be that products that you researched commonly neglect people who lack sufficient mobility (perhaps due to arthritis), or a sensory lack (e.g., poor vision) to use a the products. You can start to address that by expanding the description of the end-user group to explicitly include people with arthritis or people with poor vision.

Example: an expensive but mature technology is used. Perhaps the researched products seem too costly compared to other classes of products that use similar technology. (e.g., a \$1,000 standing house lamp that uses \$2 LED technology.) In this case, the users who are excluded are those without the money to buy the lamp. You can start to address this problem by expanding the description of the end-user group to explicitly include people of lower incomes (you should specific a target for the minimum income level).

At this stage, you would update the user group descriptions, being careful to ground your justifications for changes in research you've done and facts you know about what is and what is not possible and reasonable.

However

In academic settings, you will likely lack the experience and resources to fully describe all the user groups. This matter is simplified here - but recognize that these allowances are made only because of the academic setting.

  • End-users and co-users must be fully and appropriately characterized to “marginally meet educational expectations”1).
  • Additionally, characterizing and designing for manufacturing, maintenance, and end-of-life user groups is necessary to “meet educational expectations”2).
  • Additionally, characterizing and designing for at least one other user group is necessary “exceed educational expectations”3).

bugcatcher.jpgFig. 1: Humanely dispose of bugs...

User groups are not necessarily rational, and certainly never perfect4). The irrational nature of user groups is often manifested in their preferences for products.

pidgeonwars.jpgFig. 2: ...but DESTROY ALL pidgeons!

A given user is generally predictable. But groups of users can exhibit behaviours that are inconsistent. Consider the bug catcher shown here, which is used to humanely capture house pests like bugs and spiders, and then release them safely outside the house. While this is perfectly reasonable by itself, it becomes a problem in light of the pigeon-killing device that often adorns windowsills in city buildings.

The question is: how does the designer deal with the paradox of users who are happy to let spiders live but torture and kill pigeons? This kind of problem cannot be predicted, which means designers must be flexible enough to respond quickly depending on the circumstance.

Deliverables

As of 2019, we no longer require explicit description of user groups in design projects.

You must document who the user groups are, how they are characterized, and how you expect them to want to use your design intervention. This information will be vital in subsequent stages of the design process.

It is sufficient to use extended point form, as done in the examples above. Basically, name each user group, and list their most significant characteristics. The most important thing is to capture the most significant differences between the user groups with respect to the specific design brief you are working with.

When you're revising user groups, be sure to state clearly what has changed, and why you changed it. Simply writing down an altered user group description is not enough; you must be able to defend your rationale for the alterations.

See Also

Exclusion Calculator
This tool, developed by the University of Cambridge, helps designers determine how many people are excluded from using an intervention based on common abilities and disabilities. Statistics are based on the UK population only, but it remains useful for roughly estimating exclusions in most developed nations.
1)
This is a polite way of saying “Pass the assignment”.
2)
This is roughly the “average” to “good” range of marks in this category.
3)
That is, to achieve “excellent” marks in this category.
4)
See bounded rationality for more about the imperfect nature of humans as reasoning agents.
design/user_group.txt · Last modified: 2020.03.12 13:30 (external edit)