Over four million miles of roadway span the United States. A driver in southeastern Florida City, Florida could hop in her car and 50 hours later step out into northwestern Blaine, Washington 3,435 miles away. Despite her long journey, she would have a remarkably consistent drive. She would travel on 12-foot wide interstate lanes constructed of approved asphalts, aggregates, and finishes.¹ She would view highways signs fabricated from specified microprismatic sheeting and retroreflective paints. She would obey a nearly uniform set of traffic laws. She would experience a system that allows widespread access by nearly every shape, size, and make of vehicle, from Mazdas to Maseratis, from semi-trailers to school buses, from tower ladder fire trucks to Harley Davidson Fat Boys.

Imagine if you awoke tomorrow morning and this system had suddenly changed. Highways were six feet wide. Roads were constructed of gooey tar and jagged rocks. Speed limits were written in tiny, white text on light gray backgrounds. Traffic laws were state secrets. This system would no longer support your needs, making your travel both difficult and dangerous. You could no longer easily get to work, visit a grocery store, or reach a hospital. How would your life change?

Although this thought experiment may seem farcical, one out of six Americans faces similar dilemmas every day. They encounter systems that do not support their needs. They confront challenges to get to work, visit grocery stores, reach hospitals, ascend stairs, read books, play games, order takeout, understand conversations, exchange currency, negotiate contracts, download a mobile app, or use an e-commerce website. They have a disability.

Merriam Webster Dictionary defines a disability as “a physical, mental, cognitive, or developmental condition that impairs, interferes with, or limits a person’s ability to engage in certain tasks or actions or participate in typical daily activities and interactions.” Seems fitting. However, the activist and disability pioneer Dr. Henry Viscardi described it another way: “There are no disabled people. We are all just temporarily abled.”

Viscardi’s definition is equally applicable today. We are all a broken bone, damaged DNA strand, or high-grade fever away from being disabled, be it for an afternoon or a lifetime. Disability ranges from a sprained wrist to severe cognitive dysfunction, and includes vision loss, color blindness, deafness, paralysis, scarring, seizures, neurological disorders, speech impediments, dyslexia, ADHD, and social and emotional issues. Even glaring sunlight or a blaring alarm is enough to disable us temporarily. Try viewing a text message when walking out of a dark theater. Try listening to a voice mail when standing in the middle of a rock concert. Disability need not be permanent to be total.

Although the range of disabilities is broad, one thing is consistent—the desire for accessibility. Accessible products and services allow all people to fully enjoy and participate, bypassing limitations and frustrations, transforming dead-ends into on-ramps.

With its quiet simplicity and inclusive design, GOV.UK provides an accessible repository of government services and information to all UK citizens. The website supports a full range of screen readers, screen magnifiers, and speech recognition software. A person may order audio CDs, Braille documents, and large print versions of the website’s content. Eschewing heavy-handed visuals for fast-loading pages, the website’s user experience excels on both desktop and mobile devices. Clear, contrasting text make reading a breeze. And, perhaps most importantly, the website’s designers do not rely upon intuition—they regularly test accessibility with real users, including those who have physical and mental disabilities .

Compared to the public sector, private businesses often fall short when designing accessible websites and apps. Accessibility may be handled only during the last stage of a project, like a steamroller that flattens and smoothes over the most erroneous errors, filling in the potholes of an experience. Creators sometimes misconstrue accessibility as a cost rather seeing it for what it is: a potential profit center.

Accessibility is not altruism. It is instead an acknowledgement that different people have different needs—a foundational concept underpinning both UX and business. A business might go bankrupt if it refused to serve anyone working within the mining, construction, and the manufacturing sectors. Yet, an inaccessible app or website would underserve roughly the same percentage of people: 12.8%² of all Americans. For the sake of market share alone, accessibility makes good business sense.

Smart companies serve both the explicit and implicit needs of users. A person can activate Speak Screen narration ³ on Apple iOS devices (see Figure 19-1), vocalizing the text of a website or app. When paired with Bluetooth-enabled hearing aids, a person could hear the narration without broadcasting her interests across a room of strangers.

Microsoft Xbox allows players to form an Xbox Club, a group of like-minded players who may or may not share a disability. In addition, players with limited mobility can utilize Xbox’s adaptive controllers⁵ to enhance their experience through customizable, oversized controls. What better way to spend a lazy afternoon than to pair up with trusted friends and climb the leaderboards of Forza Motorsports?

When we improve accessibility for disabled users, we enhance the lives of all users. OXO Good Grips kitchen tools were designed for people with arthritis,⁶ but everyone likes big, easy-to-hold handles. Sidewalk curb cuts gently transition between streets and sidewalks, helping the 6.8 million Americans who use a wheelchair, cane, or crutches⁷ (see Figure 19-2). They also help people riding bicycles, parents pushing strollers, and delivery drivers pulling dollies. Closed captioning helps the reported 20% of Americans with hearing loss.⁸ It also allows everyone to follow a story in noisy restaurants and airports.

Accessibility grows increasingly necessary as the digital natives of today become the aging populations of tomorrow. Both deserve a good experience. We all do.