There’s a brief moment during the first round of user testing that I absolutely love.

The very first subject is scanning the screen and thinking out loud, understanding, dissecting, validating or rejecting. I sneak a peek at my client, and catch a tiny smile, eyes wide and eyebrows raised.

The experience we’re witnessing is invaluable, and he knows it.

This is the moment where he realizes that iterating on a product in the design phase is not merely uncovering a few blemishes, but qualitatively improving his product. Had he attempted this during development, the cost in both time and dollars would have been orders of magnitude greater.

How do we do it? After an intense week of discovery and rapid collaborative design, we create a fairly high-fidelity prototype and we use it to test our riskiest assumptions. Armed with the results, we’ll improve and re-test, refine and re-test, and in a matter of weeks we’ll be ready for technical development with a high level of confidence in our design.

There’s no terrifying unveiling of a mockup I’ve been designing in a cave for weeks, headphones on, making my best guess at what will work and praying it will be accepted by the client. No dog and pony show. No crowd-goes-ahh (or crowd chases me out with pitchforks). In fact, the whole process is relatively (and refreshingly) surprise-free.

Designing and refining a prototype collaboratively is an incredibly powerful process. We have buy-in throughout the process from key decision makers, the development team, and even potential customers. We often significantly improve upon the original concept. And most importantly, our clients avoid the potential for a costly investment in a product that no one will use.

And that’s exactly what that tiny smile is all about.