Among all the requirements that a startup can place on a prototype, efficiency rules. Founders compete to carry their company and their product as far as possible, with as little as possible. Unfortunately, this can lead to strategies that restrict the building of physical objects to what is deemed "absolutely necessary".
In his book Fooled by Randomness, Nassim Nicholas Taleb tells the story of a performance analyst who reviewed a Wall Street firm’s investment performance over several years. He found that only a few percent of the traders’ investments resulted in truly large gains, while the rest of the investments had little return. The analyst’s recommendation? Tell the traders to only invest in the opportunities that would have a large return.
The obviousness of an investment’s value in hindsight makes it tempting to believe that trading decisions could have been better managed beforehand. This same temptation appears in design. Looking back on a series of developments, builds and decisions, the path from concept to final product can be mapped out clearly. The projects that were built out, but never used, appear as wasteful in hindsight. Designers are then told to only build the “valuable” prototypes, just like traders are told to only invest in the high return opportunities.
This emphasis on hyper-lean, optimized building pushes teams into dangerous biases. The easiest way to ensure that something is built efficiently is to build what you already know using materials and skills you have on hand. This runs directly counter to what prototyping should be about: building to learn something you don’t know, using the methods and materials most likely to give you the answer you really need. Focusing on a small number of “optimized” builds also pushes designers in directions they already feel are successful, even though there may be little real evidence to support it. With fewer builds, each outcome weighs more heavily in the overall decision-making pathway, compounding that bias further.
Efficient prototyping is not about minimizing builds, but maximizing what can be learned early, using lower cost methods, and minimizing the risk of last-minute design changes. I have several industrial design colleagues who work at the earliest stages of product concepts. They are masters of the 30-second prototype, rapidly producing dozens of shapes in foam and paper to explore all the potential dimensions of a new idea. Each physical object rapidly adds detail to the path the design should go down. Even more importantly, these builds highlight paths that should not be taken, efficiently pruning less effective concepts and revealing failure modes that will need to be addressed. And yet, every industrial design individual or firm has stories about clients that have grilled them over the need for these builds or have pushed them to slash billed hours to the bare minimum. Clients press to save a few hundred dollars, while blithely exposing themselves to six-figure design risks six to twelve months later.
We can illustrate this with a little math. Pretend you are developing a small handheld electronic device. It has a plastic case, one or two simple electronic PC boards, a battery, and some buttons. You start building shapes from foam, graduate on to 3D printed cases with off-the-shelf parts, then eventually raise the capital to buy your volume tooling and secure bulk purchase agreements for all your standard parts. At each stage, you get input from potential customers, from your marketing team, and a range of experts from manufacturing to sales channels. You start with a large number of cheap builds and progress to fewer and fewer cycles as the builds increase in sophistication and cost. Ideally, your final design smoothly transitions to manufacturing, goes on the market and becomes an instant hit.
Now imagine you try to go “lean” too early. You cut your early builds in half, but still make it through your product validation. As you head into pilot production, your marketing team calls. They showed the concepts to a larger group and just discovered that the case design mimics a highly popular product in Japan. Between the potential IP litigation and branding confusion, the current form factor is a no-go. You call an emergency meeting with your design firm and ask them to do what they can without changing any of the internal electronics.
Miraculously, they get you a new, workable design within four weeks. You pay a premium, but your product is ready in time for the holiday season and sees some moderate success as a popular gifting items for office workers. You get a call from a corporate gift branding platform early in the next year and hear some of the best news possible. They want to place an order, for millions of units. Their purchase order in hand, you go hunting for a volume manufacturer. You find an amazing partner with capacity and start going down your list of suppliers with the good news. Unfortunately, you PC board maker has some bad news in exchange. Several major components are in short supply. You find alternatives, but you’ll need to revise the board. It’s doable, but only if you shift some of the case dimensions. Your earlier design had left room for this contingency, but the extra space requirement was lost in the frantic rush to make the product launch date.
These situations are extremely common. Most startups and product managers consider themselves lucky with only a single late-stage design change. Will doubling the number of early builds eliminate the risk? Probably not. But when changes result in six-figure cost increases and months of delay, reducing the risk of that scenario by even 10% easily offsets the extra few thousand dollars spent in early builds.
Ultimately, an efficient build program should result in a reduced overall cost, not just reduced spending at a specific stage. Founding teams that brag about their minimal builds as part of their pitch to investors are waving a red flag. It’s perfectly fine to show off a single, beautiful prototype that appears to have sprung magically through a chain of efficient builds during a pitch. That’s just good story telling.
But at some point, I will want to visit their workspace. I will be looking for bins of foam models, notebooks full of sketches, and messy work benches cluttered with dozens of dead ends. I want to know that they have systematically chased down multiple options before arriving at their current stage, while the chasing was still cheap.
Have you ever had to work out a budget for early prototypes? Start by working on the budget for late prototypes. It can be hard to quantify the "value" of early builds based purely on what you think you might learn. Instead, estimate how much it would cost to redo a design element a year in the future, and how much reducing that risk by even 10-20% would be worth.
About this Series
This is the seventh installment of a ten-part series on prototyping strategy. This is not about how to pick a 3D printer or get a nice finish on your painted parts, but a deeper reflective dive into the why and how we go about building the things that help us design better products. The points I focus on are not just to better align your project with some design "ideal", they are a way to manage the very real problem of every entrepreneur or program manager - build it fast, build it right, with as few resources as possible.