Convergent Design: why all phones are black rectangles
Today we’re going to talk about something you’ve probably noticed, but never put into words: convergent design. A quick google search tells me that this is a term I’ve made up, probably based on my past in the biological sciences, and probably from the real term convergent evolution. Convergent evolution is when living things evolve different ways to solve the same problem. For example, birds and bees both fly with wings, but how those wings came about is very different. Octopuses and humans both have nearly identical eyes but evolved fully independently (as far as we can tell*).
Why do I bring this up? The neat thing about evolution is that it uncaringly iterates on its solutions generation after generation, much like a designer iterates on their products, release after release.
So that made me wonder… given enough time, would all designers converge on the same “best” product in the same way nature finds a “best” solution? I started looking around and thinking, “boy, cell phones sure do look similar these days.” As do cars; engine in the front, four wheels, front-facing seats. Many, many other everyday items are like this. Spatulas for example- have we really already found the ideal tool for flipping pancakes, within only a few hundred years of pancake existence?**
Am I on to something in thinking that there may be a “perfect” solution for every design problem? Either we’ve already solved many design problems perfectly, or we have a lot of lazy designers copying mediocre solutions.
A Brief History of Axles and Pinions
Cell phones are a good example of convergent design, but they haven’t been around long enough to examine closely. If you’ll recall, the modern smartphone has only been mainstream for about 13 years. Instead, let’s dig into cars — most people have driven one, everyone’s been in one. Every car you’ve been in probably had a steering wheel. Every car does. Even car-ish vehicles like tractors and go-carts have them. But why? Is a wheel the ideal control system for a car? Were we really able to figure it out early on in automotive development?
As a control system, we’re talking about a circle that you spin in the direction you want to go. That’s nuts. Rotating a wheel to determine the direction of travel? The steering wheel isn’t even on the same axis as the car wheels. You might be thinking “Steve, it probably was just the easiest way to connect a control to the turning axle of the cars”, but that’s wrong. The first (and probably simplest) system for controlling cars was a tiller, similar to how you’d control the rudder on a boat. Furthermore, if the use of a steering wheel was purely for technical simplicity, why wouldn’t we have updated with our modern technology by now?
1904 Cyklonette with tiller steering.
This article isn’t about car design, so I’ll skip the history lesson. Steering wheels were inspired by ship wheels, which is why they rotate left and right. They were invented in 1894 by French engineer Alfred Vacheron, and they were replacing tillers by the start of the 20th century. Steering wheels offer more control, and the best design won out. Nowadays it’s still the best design, but for other reasons. The ability to make subtle adjustments makes it ideal for driving at high speeds, and it’s a great shape to hold an airbag in the middle.
Steering wheels seem like a pretty good argument for convergent design. But are design solutions always this obvious? Is there an opposite case, where there’s no single “ideal” design? What problems have resulted in radically different solutions that have totally diverged from each other?
Divergent Design
Take chairs for example, most people have sat on one at some point. There’s nearly every type of chair you can imagine; stools, recliners, couches. But are these examples of true divergence? I’d say each one is the perfect solution to a different category of seated needs- compact, for relaxing, or for multi-person seating respectively.
It’s hard to find examples of designs that wildly diverge from each other because when a product works, it tends to get imitated by competitors. We have Apple to thank for all phones converging on a black rectangular form. Their original iPhone defined the smartphone genre and still does. A large rectangular screen with minimal buttonry is the best solution to the problem, for now. Competitors who bring a less good solution to the market (looking at you, Microsoft Zune) get forgotten. In nature when evolution fails, the animal dies and doesn’t make it into the fossil record.
The original black rectangle.***
The easiest way to see divergent design is in modern emerging industries, such as the future of retail. Some stores have adopted self-checkouts, others have shopping carts that ring up items as you shop. Amazon has its camera-based solution. These are all pretty divergent. Which is the best? We’ll probably find out in a few years when it starts showing up everywhere.
Space tourism, virtual reality devices, drones, and smart city technology are all industries that have divergent products trying to accomplish roughly the same thing.
I get to see a lot of start-ups in my work, and they often have new products that solve a need not currently met. If those products become a commercial success, it’ll probably be copied and tweaked by others. The original product will get tweaked by the inventor. Over time, it’ll change, but it won’t change that much. Just like designers iterating, and nature evolving, products make incremental changes. The steering wheel changes, but it doesn’t stop being a steering wheel. Successful products change, but they don’t diverge.
This explains why we only have one system for controlling cars. It’s much easier and safer to tweak something successful than to try and jump to the next major success. Evolutionary design is much faster and easier than revolutionary design. In terms of the most money for the least effort, it’s better to copy and tweak.
Convergent Conclusions
So, given enough time, would design always converge on the same solutions? Absolutely not. Two reasons:
1. Design problems don’t like to stay solved.
Design problems change over time, and new needs are realized. The needs of the steering wheel were changed when airbags were invented, so they were tweaked to fit one in the middle. Old needs that were originally glossed over (frequently the case with accessibility) are considered. If you’re redesigning a webpage that was built before modern accessibility guidelines were published, you’ll have to take that into consideration.
2. Designers are lazy.
Designers and inventors build off of each other’s work, are influenced by their culture and current events, and enabled by technological innovations. Good designs are picked up, spread around, iterated and improved- often without changing anything major. People, and the societies that use the products, are always changing. Reinventing a product is hard, and has a much lower rate of success. Finally, estimating the “similarity” of two different products isn’t exactly scientific. An app develop might see android and iOS as radically different, but a layperson would just see them as mobile operating systems.
What’s my point then? We should always be rethinking our solutions and trying new ideas, just as crazy engineers were doing when they put a ship’s wheel into an automobile. We need to keep rethinking our solutions and avoid assuming our grandparents’ spatula is the best way to flip our modern pancakes.
There will never be a single unifying theory of product design that services every need. But that’s okay.
Because it means I’ll never be out of a job.
* The comparison is actually between the phylogenetic classes of cephalopods (squid, octopus) and vertebrates (tigers, birds, humans- anything with a spinal cord). The eyes aren’t perfectly identical, cephalopods didn’t evolve a blind spot. Further reading.
** When I say pancakes I mean fluffy American griddle cakes. You can keep your fancy French crepes.
*** Original (unedited) image by user Ascola via Wikimedia. Licensed under CC-BY-SA-2.0
Further Reading on Convergent Design: Why does everything look the same? By Isaac Fagerli
