Rules of Prototyping

Prototyping is a critical phase of design thinking where ideas are tested and refined. It's a mentality of provisional attachment to ideas, where you are willing to let go of a "darling" idea if it doesn't perform well. Prototyping is about learning as much as possible, as quickly as possible.

Key Rules of Prototyping

1. Do the Last Experiment First: When you have multiple hypotheses to test, start with the one that is most difficult or most likely to fail. This is the opposite of the typical approach of doing the easy things first. If the most difficult hypothesis fails, it saves a lot of time and effort from being wasted on a project that was doomed from the start.
   • Example: With the first ATMs, the most critical hypothesis was whether people would be comfortable taking cash from a machine on a street corner. The developers addressed this by creating a facade of an ATM with a person hidden behind it dispensing cash. This experiment proved that people were willing to trust the machine, allowing the team to focus on the technical details.
2. Maximize Learning per Unit of Time and Money: Prototypes should be designed to yield the maximum amount of learning for the least amount of investment. This is an agile, iterative approach where you pack as many experiments as possible into a short period.
   • "Quick and Dirty" Prototyping: The goal is to use readily available materials to quickly test a concept. For instance, to determine the optimal size of an iPhone icon, Apple developed a game that tested how quickly users could tap on icons of different sizes. This quick and dirty prototype, created in a high-secrecy environment, led to the discovery of the ideal size.
3. Fail Faster to Succeed Sooner: The philosophy of prototyping is to be okay with being wrong the first time, or even the second or third time. The quicker you can fail, the quicker you can learn and iterate toward a successful solution.
   • Examples:
     • James Dyson created over 5,000 prototypes for his bagless vacuum cleaner, constantly failing and learning until he perfected the design.
     • Thomas Edison famously said that he didn't fail 10,000 times to create the light bulb filament but rather discovered 9,999 ways it wouldn't work.
   • Embracing Failure: Companies like IDEO maintain a "tech box" of failed prototypes, recognizing that an idea that fails in one context might be perfect for another. The failed Google Glass, for instance, led to the highly successful Google Lens. This mindset of accepting failure as part of the learning curve is essential for innovation.