One of the biggest flubs that product teams make is confusing designs that look great with designs that actually work well. It’s a simple mistake, but it can have grave consequences: If your product doesn’t work well, no one will even care how it looks, after all.

The best way I’ve found to get around this confusion is a technique called story-centered design. The idea is to create a series of narrative use-cases for your product that illustrate every step in the user’s journey through it. I’ve used this technique with dozens of startups and it always helps teams move past the surface visual details to make better decisions on what really matters: how their product finally works.

Designs shouldn’t be blueprints

I’ve observed that teams often like to walk through UI designs as they would a blueprint – showing where each element belongs on the plan. Each screen shows how the product might look in a different situation, but the screens are not connected in any way. The problem is that when designs are presented this way, you’re only building an understanding of how the product looks. You’re not focusing on how the product works, and you’re not simulating how customers interact with it. So when teams critique designs as blueprints, it severely limits their ability to reason through the interactivity of the product.

The best product designers practice story-centered design. They begin by crafting stories that show how customers interact with a product, and only after they’ve accomplished that do they design screens as a way to tell that story of interaction.

The process of designing by story

In story-centered design, teams critique work by looking at dozens of sequential mockups that function like frames in a filmstrip (see the photo below). Designers present every sentence the customer reads, every action they take, and every screen that system generates in response. The designs follow a customer from an initial trigger all the way through completing a goal, and they show how the design supports every step in that flow. I’ve coached many startups through story-centered design exercises and seen these techniques work for mobile apps, marketing websites, analytics dashboards, enterprise IT and beyond.

For engineers, this should sound familiar. The core of story-centered design is the same as test-driven development. Only instead of writing tests to exercise our code, we’re creating stories to exercise our designs. Just like test-driven development, story-centered design can have an incredible impact on a team’s execution speed and product quality.