The purple ones

A pattern emerged interview after interview:

When asking users about their favorite coffee, they rarely remembered the official names. They referred to them by color instead. We could see them squint, think for a bit, and go: "The purple ones."

Later, in usability tests, the pattern held. We would ask users to add the coffee they usually buy to the basket, and they wouldn't read the names at all. They scanned the product list by color and tapped.

Mental model mismatch

Capsule names like "Arpeggio" or "Stormio" do real work at the brand level. They're distinctive, premium, ownable. They're just hard to recall at the moment a returning customer is trying to find their usual coffee. Users filled the gap with what they could see: color. This is the kind of pattern that only shows up in research.

The design sprint experiment

During a week long design sprint we had the opportunity to test a bunch of fresh ideas at once. Guillem Linares and I put together a list of hypotheses and observations from existing user data and let those drive the design. The color mental model was put at the center of the experience, but that was not all.

So we built an end to end funnel, simulating the most common user journey, from the homepage to the final checkout.

The sprint version of this prototype was made with Figma, the way most sprints work. For my portfolio, I rebuilt the whole thing in code with Next.js, real motion, real transitions, and real touch behavior, so anyone reading this could feel the design instead of clicking through static frames.

Try purchasing some capsules with this prototype:

Prototyping is changing fast, with AI we can now build projects like this one in a few hours. Results are much more accurate & measurable than they used to be with Figma.

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Measuring success

We ran an unmoderated test with eight frequent Vertuo buyers, all fitting the persona we had been designing for. For each hypothesis we picked metrics that could prove us wrong, not just confirm what we wanted to hear.

Hypothesis 1: the color grid

We asked each participant to find and add their favorite capsules to the basket, starting from the homepage, and then to filter the grid by color. We also asked how easy the browsing experience felt on a five-point scale from very complicated to very easy.

Hypothesis 2: the subscription funnel

We asked each participant to move to checkout once they were done adding capsules, and then to complete the purchase, watching whether anyone explored the subscription option on their own. Afterwards we backtracked and walked them through the value proposition explicitly to see if it landed.

Organic engagement during checkout was low, which tracks with how upselling usually performs in e-commerce. The more interesting signal sat one step deeper: half the participants found the offer worth considering once it was framed, which is a different question than whether they'd notice it on a busy day.

Qualitative Feedback

Beyond the numbers, we asked how they felt about the overall look and feel of the page, the colors in the grid, the option to filter by color, and the value proposition of the subscription. We were listening for surprise more than approval.

Most users called the page calmer than what they were used to, and the color filter landed without anyone needing it explained, which was the bigger signal: it was already how they thought about the products.

The half who liked it valued a better process for recycling, the discount and not having to think about reordering. The half who didn't enjoy the small ritual of picking capsules each month, which is fair, the subscription is a service for one mode of behavior, not all of them.

Conclusions

Design sprints are a great way to step out of the regular cadence, test ideas that wouldn't survive a normal roadmap conversation, and work with people you don't usually sit next to. Just a problem and a deadline.

Separate teams are currently testing the color filter and a semantic search where typing "blue" surfaces the blue capsules, "strong" surfaces the high-intensity ones, and so on. A different shape, same mental model underneath.

The subscription upsell at the end of the purchase flow is in the pipeline to be tested next. Big-company timelines being what they are, the prototype raised enough eyebrows in the right rooms that the idea is being seriously considered. That's already a useful outcome for a week-long sprint.