How accessibility users drive better product development

User-centric design is a methodology that instructs professionals to develop product strategies with the user in mind, considering their needs and pain points. However, it's crucial to understand what user we're talking about and whether a single user can adequately represent the entire audience. We'll try to break it all down in this article.

Average users, persona analysis, and extreme users

While creating a product, we often focus on a so-called “average” user and build customer journey maps based on their experience. However, this approach has its limitations: it can prevent deeper understanding of diverse user needs and inadvertently excludes a wide range of people from engaging with the product. 

These limitations have led to the rise of audience segmentation, which supports more personalized product solutions and marketing activities. One common method is the use of personas: a technique that involves creating detailed profiles of different user segments. This helps teams understand how various users interact with the product, what needs it fulfills, and what improvements they might expect. Personas are typically based on common traits within the target audience, such as demographics, industry, purchasing habits, and user behavior.

The extreme user approach goes a step further by focusing on atypical or “non-average” users. These individuals have needs and challenges that go beyond those of the average user. They may use a product in unconventional ways: through assistive technologies or alternative usage patterns, which can uncover edge cases, product flaws, and untapped opportunities. Insights from extreme users often spark experimentation and innovation.

A great example of an extreme person is someone from a sensitive or underrepresented group, for instance, an older adult, a person with a disability, or someone for whom English is a second language. In this article, we’ll focus specifically on the experience of a person with a disability, and explore how their interaction with a product can lead to better, more inclusive product development.

The Curb-Cut Effect

There is a concept in accessible product development called the Curb-Cut Effect, which describes how something originally designed for people with disabilities can end up being beneficial for everyone. This term originated in the 1970s when students with disabilities at UC Berkeley protested for greater mobility and independence. As part of their efforts, they built handmade curb ramps to make streets more navigable for wheelchair users. Over time, these ramps proved useful not just for wheelchair users, but also for people with luggage, parents with strollers, cyclists, workers with carts, and older adults.

Below are four other examples of how products initially designed for specific groups have ended up serving a much broader audience:

1. Audiobooks

Originally known as “talking books,” audiobooks were introduced in the 1930s as part of the Talking Books Project by the American Foundation for the Blind and the Library of Congress. The goal was to provide accessible reading materials for World War I veterans and others who were blind or visually impaired. By the 1970s, audiobooks gained popularity among the general public, especially with the rise of audiocassettes. Today, they are a staple of virtually all music streaming and book platforms.

2. Parking sensors

Parking sensors were adapted from a technology originally designed to assist blind individuals in navigating unfamiliar environments. Known as Electronic Travel Aids (ETAs), these tools converted visual information about obstacles into audio or vibration feedback using infrared sensors. This same principle was later applied to vehicles, helping drivers detect obstacles and park more easily.

3. Electric toothbrushes

The electric toothbrush was invented in the 1930s by a Swiss dentist for patients with limited hand mobility due to injury, age, or disability. These individuals had difficulty using a manual toothbrush effectively. It soon became evident that electric toothbrushes were not only more convenient but also provided a superior clean for everyone. Today, they are a standard tool in dental care.

4. Vegetable peelers

A classic example of inclusive design is the modern vegetable peeler. In the 1990s, the company OXO launched its Good Grips line, featuring kitchen tools with wider, rubberized handles specifically designed for people with arthritis. Collaborating with the American Arthritis Foundation, the company tested prototypes with volunteers and refined the design to improve grip and usability. These ergonomic handles quickly became popular with all users and are now widely considered an industry standard.

Accessible tech features that are convenient for all

Do not call

Delivery and taxi apps often offer limited communication options between drivers/carriers and users. In many cases, calling is the only available method, with no in-app chat. While calling may seem convenient for the “average” user, it makes the app completely inaccessible for deaf individuals.

Deaf users are a prime example of extreme users who interact with products in unique ways. A product manager might question whether building a chat feature for a small group of users is worth the investment. However, enabling chat communication can benefit a wide range of users, including:

• People with non-standard speech (e.g., speech impairments or non-native English speakers)
• Parents with sleeping children who don’t want to answer a phone call
• Users ordering food during meetings, in libraries, or other quiet environments
• People who simply prefer not to talk on the phone.

Leave at door

Many delivery apps require couriers to hand off packages directly to the recipient. At first glance, this seems like a safety feature, but it can lead to complications. What if the user is in the shower? In a meeting? Wearing headphones? Or has limited mobility?

The “Leave at Door” option gained popularity during the COVID-19 pandemic and has since become a standard feature. It benefits a broad user base, including:

• People working from home who can’t interrupt meetings
• Wheelchair users who may need more time to answer the door
• Anyone who wants flexibility and less interruption.

Avoid the stairs

Most navigation apps provide route options by car, public transport, bike, or on foot. However, the “on foot” route typically lacks accessibility filters. An “Avoid Stairs” feature, often assumed to be relevant only to wheelchair users, actually helps many others:

• People using scooters
• Travelers carrying heavy bags or suitcases
• Parents pushing strollers
• People using crutches due to temporary injuries
• Seniors
• Wheelchair users.

Once again, a feature designed for a niche group proves useful for many.

Fonts magnification

Both Android and iOS allow system-wide font scaling, but many apps are not optimized for large font sizes. This oversight can result in broken layouts, making apps harder to use and limiting accessibility.

Scalable fonts benefit a wide range of users:

• Seniors
• People with low vision
• Users who simply prefer larger text for comfort.

Dark mode

It may come as a surprise, but dark mode is also an accessibility feature. It offers benefits across multiple user groups:

• “Average” users scrolling in low-light environments will find dark screens easier on the eyes
• People recovering from eye surgery, where exposure to bright screens is discouraged
• Visually impaired users, many of whom are light-sensitive and may experience discomfort or pain with bright screens
• Users with mental disabilities, for whom bright screens can be overstimulating.

Inclusive design and product personalization 

Inclusive design might sound like a fancy concept, something only big tech companies can afford. In contrast, product personalization has been around for quite some time and is now a standard practice for product managers, designers, developers, and marketers alike.

Today, nearly every app offers a wide range of product personalization options. For example:

• A hotel booking app allows users to select their budget, star rating, number of rooms, floor preference, available amenities, whether food or airport transfers are included, and whether the hotel is pet-friendly.
• A flight booking app lets users choose between direct flights or those with layovers, whether baggage is included, preferred travel class, and more.

We’ve also grown accustomed to AI-powered recommendations in e-commerce and food delivery apps. These personalization features are now expected, and even criticized if missing.

However, while such customizations have become the norm, basic accessibility features like font scalability or subtitles for video content are still treated as optional add-ons, even though they are far more critical to user experience for some individuals.

It may be helpful to reframe product adaptation for extreme users as a natural extension of product personalization. Doing so not only improves accessibility but can also expand your user base and unlock new revenue streams.

Conclusion

When prototyping interfaces, we often design with users who look, think, and interact with the world like ourselves, simply because that’s the experience we know best. But this narrow perspective limits a product’s potential to serve a broader, more diverse audience.

From an ethical standpoint, this approach excludes many people and denies them opportunities that our products could provide: whether it's learning a new skill through an edtech platform, ordering food online, or navigating from point A to point B. From a business perspective, it means missing out on a large segment of potential users who would gladly pay for services tailored to their needs.

Building product strategies that include extreme users leads to more robust, innovative, and inclusive solutions. It creates a more loyal and satisfied user base: where no one is left behind.