Testing Mind Map Series: How to Think Like a CRO Pro (Part 70)

Carlos Trujillo
By
February 4, 2025 ·

Interview with Carlos Trujillo

Every couple of weeks, we get up close and personal with some of the brightest minds in the CRO and experimentation community.

We’re on a mission to discover what lies behind their success. Get real answers to your toughest questions. Share hidden gems and unique insights you won’t find in the books. Condense years of real-world experience into actionable tactics and strategies.

This week, we’re chatting with Carlos Trujillo, an agency founder and Experimentation consultant, leading projects for more than 100 brands in multiple regions and verticals.

Carlos, tell us about yourself. What inspired you to get into testing & optimization?

After being in digital marketing and ecommerce for about a decade, I recognized experimentation as a field I wanted to specialize in driven by the idea of blending creativity and applied science for business decision-making.

The idea of quantifying the real impact of innovation initiatives really resonated with me, and I haven’t looked back since!

How many years have you been testing for?

I’ve been involved in digital experimentation in various capacities for about a decade. However, at a professional level, I’ve been specializing in it for four years, since 2021.

What’s the one resource you recommend to aspiring testers & optimizers?

CXL’s Conversion Optimization Minidegree

Answer in 5 words or less: What is the discipline of optimization to you?

A way to innovate systematically

What are the top 3 things people MUST understand before they start optimizing?

  • Correlation is not causation
  • It’s common to make things “better” and yet not influence a shift in user behavior
  • Launching tests is easy; getting trustworthy results is the hard part.

How do you treat qualitative & quantitative data to minimize bias?

As a rule of thumb, I try to get someone else involved in analyzing the data sets if I’m too familiar with the business. Familiarity is always a breeding ground for biases.

Whenever possible, I recommend having different teams (incentivized differently) ideate experiments and analyze them. Otherwise, there’s a big conflict of interest if those in charge of influencing business growth analyze their own work.

At a more philosophical level, something I try to do with both qualitative and quantitative data is limit the insights to what’s truly observed. There are so many stories we can create around a limited sample of data, so it’s always a good practice to avoid being delusional (or cherry-picking numbers).

How (to you) is experimentation different from CRO?

To me, experimentation is the act of systematically running trustworthy tests, with its goals centered on the practice of testing itself.

CRO, on the other hand, is a broader discipline aimed at driving business growth. While it involves experimentation, that’s just one part of it—much of the work focuses on user research and ideation.

In the most mature organizations, those responsible for experimentation are typically focused on the trustworthiness of results rather than the outcomes of the tests. This is a key distinction, and even smaller companies should begin adopting this mindset to some extent.

Talk to us about some of the unique experiments you’ve run over the years.

I’ve been privileged to see the results of many tests through my work at Speero, and some of the most fascinating ones are the counterintuitive ones.

Here are a couple worth highlighting:

  • We tested introducing an alternative payment gateway (with lower fees) on an ecommerce store. At first, it seemed like a no-brainer for the business to make the switch. However, we found that it wasn’t a good choice due to a very high rate of rejected payments in international markets. The final decision was to stick with the old gateway, despite its higher fees.
  • Qualitative data (onsite polls) revealed that users strongly disliked a cross-sell popup that appeared after adding a product to the cart. We tested removing the popup from the user journey, expecting it to improve the experience. Surprisingly, this change significantly reduced revenue per visitor, proving the popup’s business value. It was a great reminder of the importance of combining different data sources for better decision making!
CRO Expert Profile Carlos Trujillo

Cheers for reading! If you’ve caught the CRO bug… you’re in good company here. Be sure to check back often, we have fresh interviews dropping twice a month.

And if you’re in the mood for a binge read, have a gander at our earlier interviews with Gursimran Gujral, Haley Carpenter, Rishi Rawat, Sina Fak, Eden Bidani, Jakub Linowski, Shiva Manjunath, Deborah O’Malley, Andra Baragan, Rich Page, Ruben de Boer, Abi Hough, Alex Birkett, John Ostrowski, Ryan Levander, Ryan Thomas, Bhavik Patel, Siobhan Solberg, Tim Mehta, Rommil Santiago, Steph Le Prevost, Nils Koppelmann, Danielle Schwolow, Kevin Szpak, Marianne Stjernvall, Christoph Böcker, Max Bradley, Samuel Hess, Riccardo Vandra, Lukas Petrauskas, Gabriela Florea, Sean Clanchy, Ryan Webb, Tracy Laranjo, Lucia van den Brink, LeAnn Reyes, Lucrezia Platé, Daniel Jones, May Chin, Kyle Hearnshaw, Gerda Vogt-Thomas, Melanie Kyrklund, Sahil Patel, Lucas Vos, David Sanchez del Real, Oliver Kenyon, David Stepien, Maria Luiza de Lange, Callum Dreniw, Shirley Lee, Rúben Marinheiro, Lorik Mullaademi, Sergio Simarro Villalba, Georgiana Hunter-Cozens, Asmir Muminovic, Edd Saunders, Marc Uitterhoeve, Zander Aycock, Eduardo Marconi Pinheiro Lima, Linda Bustos, Marouscha Dorenbos, Cristina Molina, Tim Donets, Jarrah Hemmant, Cristina Giorgetti, Tom van den Berg, Tyler Hudson, Oliver West, and Brian Poe.

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Written By
Carlos Trujillo
Carlos Trujillo
Carlos Trujillo
Agency founder and Experimentation consultant.
Edited By
Carmen Apostu
Carmen Apostu
Carmen Apostu
Head of Content at Convert

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