Design for one

December 08, 2011

I was drawn recently to a story on Walter Reed Military Hospital describing the engineers and doctors working on prosthetics for returning amputees from Afghanistan. The story focused on the advances in field medicine leading to greater survival rates. One uncomfortable but common question the article addressed was, “How do you decide if an injury is too horrible to keep a victim alive?” The response was, “It’s not my place to judge quality of life. We save everyone.” The result is a population of amputees many of whom have a continued zest for life and a push for engineers to make them specialized tools to perform the activities they love (tennis, cooking, etc.).

There is something powerful in designing for an individual. First, the needs aren’t generalized and the features aren’t optimized (read: averaged) for a population of users. Second, cost and manufacturing constraints don’t exist – if multiple iterations are needed, all are “prototypes” never to be mass produced. Third, judgment is quick and clear – you can see the emotional response and you can see the results in use. All of these elements create in a satisfying process of meeting a need and measuring the success in a person’s gratitude or enjoyment.

What “design for one” provides is a North Star, a tough critic, a Francine that we can’t disappoint.

Some of our most successful projects are inspired by the “design for one” (or a few). I am reminded of Project Runway’s Tim Gunn asking contestants, “who is your customer?” The answer is often, “a busy executive who moves from work to an art opening.” Way too vague, right? “Francine is my customer” is a much better answer. Sadra Medical has designed a revolutionary catheter based heart valve replacement device. Their first patient was identified and used as a beacon during the clinical trial development push and continues to be a representation of the “people they hope to help” after a successful trial. Designers and engineers can picture what she needs. She needs a quick recovery to avoid hospital induced sickness. She needs a flexible, small catheter to traverse her vasculature. She needs to survive – she has a very clear success rate: it’s either 100% or 0%.

On the other hand, projects have suffered for lack of the “one." Often ideas looking for users wander aimlessly based on where competition or opinion leads.

Can we risk letting one person stand in for a population when designing a product used by many? Probably not. Most products are intended to be used in varied environments by users separated in age, gender, education, size, dexterity, etc. What “design for one” provides, though, is a North Star, a tough critic, a Francine that we can’t disappoint. If we satisfy Francine, we’ve done our job well.