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Why do inclusive design?  download this page as PDF

The majority of new product development projects focus on time and budget. However, this focus can conflict with delivering the most commercially successful product.

There is often the perception that design effort should be minimised in order to reduce cost and shorten timescales. In reality, the true costs of bad design (such as warranty returns from unsatisfied customers) emerge later on in the product life cycle, and have the potential to cause irreparable damage to the brand image through customer frustration.

The following pages aim to demonstrate that an inclusive design approach results in better products with greater user satisfaction and greater commercial success whilst reducing product development risk.

On this page:

 
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The "Why do inclusive design" section was authored by Ian Hosking, John Clarkson and Roger Coleman.

 

Understanding ageing populations

The demographics of the developed world are changing; longer life expectancies and a reduced birth rate are resulting in an increased proportion of older people within the adult population.

In 2008, half the UK adult population were aged over 44 (ONS, 2010a). Predicted population changes up to 2018 indicate that all age groups over 45 represent emerging market segments, with 75+ being the fastest-growing age group (ONS, 2010b).

Maintaining independent living for longer is therefore essential to maintain a sustainable welfare system. The ageing population also presents a market opportunity for inclusive design.

The over 50s spent GBP 276 billion in 2008, making up around 44% of the total family spending in the UK (Age UK, 2010). In the US, the over 50s annual income after tax is estimated at USD 2.4 trillion, which accounts for 42% of all after-tax income (Immersion Active).

 
Graph showing that half the adult population is aged over 44.

The distribution of age within the adult population of Great Britain (ONS 2010a).

Graph showing stagnant markets for age groups under 45 years, but emerging markets for age groups older than 45 years.

Change in the population within each age band over time (ONS 2010b).

Further information

 

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Designing for our future selves

As people age, they often experience declining sensory, motor or cognitive capabilities. Yet increased age is also often associated with increasing satisfaction with life (see graphs opposite). Where previous generations accepted that capability loss and an inability to use products and services came hand in hand, the baby-boomer generation now approaching retirement are less likely to tolerate products that they cannot use.

“For boomers, technology is contagious. And they don't consider themselves technology dunces. Instead, they blame manufacturers for excessive complexity and poor instructions.” (Rogers, 2009)

Typically, people are viewed as being either able-bodied or disabled, with products being designed for one category or the other. In fact capability varies continuously, and reducing the capability demands of a product results in more people being able to use the product and improves the user experience.

 
Graph showing percentage of people with less than full ability as a function of their age, where percentage generally increases with age, reaching 25% for those aged over 55 and over 50% for those aged over 75.

Percentage of people within each age band that have less than full ability, as defined within the User capabilities section.

Graph showing overall satisfaction with life decreases with age during early life, and increases with age in later life. The minimum point is around age 50.

Self reported overall satisfaction with life (on a 7-point scale), derived from Understanding Society (2011).

Further information

  • A paper by Rogers (2009) for AARP: 'Boomers and technology: an extended conversation' examines how the boomer generation thinks about technology.
  • Data from Understanding Society was used to construct the graph above about levels of satisfaction. The particular data was taken from Understanding Society: Wave 1, 2009-2010 [computer file]. 2nd Edition. Colchester, Essex: UK Data Archive [distributor], November 2011. SN: 6614.
 

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The risk of bad design

Good design can happen by accident, but a rigorous inclusive design process mitigates business risk and ensures repeatable design success. In particular, understanding the diverse range of user needs can reduce the risk of undesirable and costly problems later in the product development lifecycle, such as:

  • Excessive customer support costs.
  • A large proportion of no-fault found warranty returns.
  • Lawsuits.
  • Costly rectification work required close to, or after launch.
  • Customer dissatisfaction and brand degradation.

The importance of adopting good, inclusive design principles early in the conceptual design stage is demonstrated by a report from the Design Council (Mynott et al., 1994), which found that changes after release cost 10,000 times more than changes made during conceptual design.

One costly example of insufficient accommodation of user diversity relates to the US Treasury. A court ruled that the Treasury discriminated against the blind and visually impaired by printing all denominations of currency in the same size and texture. Following this ruling, in 2011 the Treasury approved adding tactile features to US notes (Bureau of Engraving and Printing, 2011) at an estimated cost of $6.6 billion (ARINC, 2009). The Business case materials contain many other examples of avoidable business costs.

 
Image showing that US dollar bills are all the same size

At an estimated cost of $6.6 billion, tactile features will be added to US notes, because the existing notes discriminate against the blind, as they are all the same size.

The cost of making changes accelerates rapidly as release approaches (Mynott et al., 1994).
Design stage Relative cost of change
Concept1
Detail design10
Tooling100
Testing1000
Post-release10000

Further information

 

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The value of good design

Advancing technologies and digital interfaces mean that products can now offer more features at relatively low incremental cost. Indeed, companies can easily fall into the trap of competing in the "feature race", trying to provide ever more features to keep one step ahead of the competition. However, increasing the number of features often hinders the usability of a device, due to the consequent increase in interface complexity and/or reduction in size of controls, symbols and text.

Philips (2010) found that the majority of Americans (63%) think technology companies don't understand their needs when introducing new products. Indeed, 39% of Americans think these companies "fall in love with their own technologies".

The impact of excessive complexity can be seen in results of a survey by Microsoft research. They asked users what they would like in the next version of Office, and found that 9 out of 10 people asked for something already in the product. (Extracted from Capossella, 2005). Other companies have delivered business success through a focus on simplicity, as described opposite.

Rather than just adding extra features, it is important to determine what functionality and features a product should include. This can provide an impetus for true product innovation and competitive advantage. An appropriate framework for achieving this is provided by inclusive design. In particular, it is helpful to set an appropriate target population and evaluate designs against the full set of inclusive design success criteria.

 
A quote from Google (2011): Our best designs include only the features that people need to accomplish their goals… Google teams think twice before sacrificing simplicity in pursuit of a less important feature.

There are many different search engines, but one in particular stands out. Google's search engine achieves ease of use through a simple, clean design. The quote above was part of the third of Google's 10 design principles in 2011: "Simplicity is powerful".

Further information

  • A report by Philips (2010): 'The Philips Index: America's Health & Well-being Report 2010' examines various aspects of American's health and well-being, including the role of technology. A pdf of the report can be downloaded from Philips website.
  • A keynote address by Capossela (2005) was part of Bill Gates' keynote address at the Microsoft Professional Developers Conference 2005. This presented survey results on what users want in Microsoft Office.
 

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Presenting the business case

An example presentation has been created as a resource to help inclusive design practitioners or supporters to tell others about inclusive design. It includes an explanation of what inclusive design is (at the highest level), why inclusive design is increasingly important in society and why it is valuable for organisations to adopt inclusive design principles.

We would encourage you to use as many or as few of these slides as needed in your presentations. Notes have been created for each of the slides to help indicate the pitch that is intended to accompany the slides and images.

The general contents of the presentation are:

  • Examples of the diversity of the world.
  • Inclusive design as a response to diversity.
  • Why inclusive design is important from the perspective of general product and population trends/demographics.
  • The commercial imperative for inclusive design and an example of the success it can bring.

You can download the business case presentation (MS PowerPoint 2003) and modify it for your own purposes. We have also made an amateur video of the presentation being given.

 
Screenshot of slide from business case presentation indicates that the UK population is around 60 million, with 11 million children, 10 million disabled, 9 million hearing impairment, 2 million vision impairment,8 Million arthritis, 3.4 million Asthma, 1.5 million Diabetes, and 14 Million Grandparents

An example slide from the business case presentation, showing different aspects of diversity evident within the UK population.

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