Why do some of the best ideas start on cocktail napkins?

Because alcohol? No.

Because they are inspired by a collaborative conversation? Yes, and…because it’s a first rough prototype.

A rough prototype is a simple expression of an idea. It might be a drawing, a paper or cardboard mockup, a storyboard, or even a pantomime or role play. It needs to be substantive enough to get the idea across and prompt engagement. Ideally, it creates some interaction such as using your imagination to step through a process or experience. It enables empathizing with the customer you’re designing for and is a quick and inexpensive way to begin design iterations.

Fast and cheap are two of the benefits of rough prototyping, and there are more.

Neuroscience has revealed some wonders about how humans respond to a rough prototype. According to Dr. Baba Shiv at Stanford GSB, when we see a rough prototype, our brain wants to help it along, to complete it, to add our own ideas to make it better. Our brain is focused on finding what’s good about the idea.

When we see a polished prototype, our brain works to critique it, to discover what’s wrong with it, and explain what’s missing or won’t work. Our brain is focused on finding what’s bad about the idea.

Furthermore, when we engage with a rough prototype and add something to it, The IKEA Effect kicks in. (Lots of good references for The IKEA Effect, I’ll let you look it up.) Even for ideas we don’t like, we might get caught up in helping it along and our brain gets invested. People tend to support what they help to create. When we add effort to something, we value it more.

This is also the wisdom behind the Silicon Valley saying, “If you want advice, ask for money. If you want money, ask for advice.” Create opportunities for stakeholders and co-creators to contribute to your idea. Ask for suggestions, acknowledge gaps, seek advice, and leverage the experience of others to vet your idea while sharing it.

Consider that your pitch might be too polished or land as too complete, inviting critiques. Stop preparing by ensuring that you have an answer for everything. Anticipate issues and use these to drive engagement with responses like, “That’s a good insight. How might we mitigate that?” Stick to storyboards and mockups as long as possible to demonstrate a mindset of experimentation, iteration, and co-creation. Draw it on a napkin!