Testing Mind Map Series: How to Think Like a CRO Pro (Part 61)

Interview with Marouscha Dorenbos

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 Marouscha Dorenbos, Analytics & CRO Director at Midsummer Agency, an agency helping international brands reach their full potential through growth and data-driven pay-per-click marketing.

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

I first encountered Digital Marketing, specifically Google Analytics, in 2015, in a small office on the outskirts of Kuala Lumpur, Malaysia. Instantly captivated, this sparked my passion for Performance Marketing. That experience then led me to secure my first official role in an agency, where my curiosity and passion for Performance Marketing naturally drew me into Testing & Optimization.

I would say that it wasn’t just my personal interest that fueled this journey. The enthusiasm of others, who may have lacked the time, projects, or analytical skills, also motivated me. Testing & Optimization feels like the cool kid in school—everyone wants to master it, but few know how!

Over the years, I also discovered a genuine love for uniting departments/activities on projects: creative, copy, analysts, PPC, SEO, and CRO. This collaborative spirit aligns perfectly with Testing & Optimization, which is incredibly versatile. We also work cross-department like that at Midsummer Agency.

How many years have you been testing for?

I first got introduced to Google Optimize around 2017/2018. I was (and am) not full time testing but I slowly started inserting it into my portfolio over the years.

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

I firmly believe that learning by doing is the most effective way to acquire new skills, as it allows for immediate application and practice. It’s unfortunate that Google Optimize is no longer available, as it was a great tool for setting up projects and running small tests, even on dummy websites. You could learn about setup, resolve potential flickering issues, and create your first test variants through it. Therefore, I highly recommend finding a free testing tool to get hands-on experience with the technical and operational aspects first.

Additionally, I suggest following Ruben de Boer’s Udemy course, “The Complete Conversion Rate Optimization Course.” While I initially learned through practical experience, Google searches, and various articles because there were no organized training materials available, Ruben’s course offers a concise and comprehensive overview of the entire CRO process. It covers everything from research and analysis to prioritization, testing, and analyzing results, providing a well-rounded understanding of Conversion Rate Optimization.

For women just starting out: I have found immense value in learning from and with other women. I participated in a data analytics course at All Women, which provided the most enriching learning experience I’ve ever encountered. They also offer courses in UX and UI, so if you’re looking to expand your skills beyond testing and optimization, I highly recommend exploring their offerings or seeking similar resources designed by and for women. Engaging with a supportive community of women, such as the Women in Experimentation Slack channel, can be incredibly beneficial, especially in the early stages of your career.

Finally, try to secure a job or internship at an agency specializing in CRO, ideally one with extensive in-house capabilities in departments that support CRO activities, such as analysis/research, UX design, and development. I also recommend seeking an agency that actively fosters employee growth through support and training budgets, and one that, of course, treats you well overall. Working at an agency with those characteristics accelerates your growth, as you’ll gain diverse experience across multiple projects and continuously learn new skills.

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

Optimize and maximize digital ROI

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

• Analysis, analysis, analysis: I can’t stress this enough. Make sure you understand what you’re analyzing. Is your data accurate or do you have tracking issues? Are there gaps in your data? Do your behavioral and feedback analyses align with your quantitative and heuristic analyses? Have you prioritized your tests based on your analysis and business objectives?
• Pre-test analysis: Have you done your homework? Can you even run tests, or does it not make sense? Have you considered alternative strategies for tests that don’t meet the required sample sizes?
• Involve all stakeholders throughout the process: While the CRO team may be experts, the clients or business owners know their business and customers best. Especially on new projects, but really on all projects, be open to client ideas and assess them before testing. You might be surprised by the valuable insights and ideas clients contribute, enriching your internal research and strategies.

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

At Midsummer Agency, we always conduct four types of analysis:

• Quantitative Analysis
• Heuristic Analysis
• Behavioral Analysis
• Feedback Analysis

We integrate these analyses to optimize our focus and efforts. By identifying high-traffic or key funnel pages through quantitative analysis, we can prioritize our heuristic and behavioral analysis, especially for large projects. This iterative approach ensures thorough examination from multiple angles.

Additionally, we leverage these analyses to gather user feedback through surveys, using insights from quantitative, heuristic, and behavioral data to inform our questions and improve our understanding.

Then of course running the actual tests is the ultimate way of ruling out bias. Unfortunately, human beings are always biased, and that’s why testing is so important to validate our insights and strategies.

How (to you) is experimentation different from CRO?

I believe there’s a considerable and understandable amount of confusion regarding terminology in our industry. When I hear “experimentation,” I think of two distinct concepts:

• Experiments ≈ Tests ≈ A/B Tests: A/B testing is just one type of controlled test.
• Experimentation: This refers to the scientific approach or methodology used to conduct experiments and draw conclusions.

For me, CRO (Conversion Rate Optimization) involves the research and analysis necessary to enhance conversion rates, which are then translated into hypotheses to be validated or invalidated through experiments.

CRO remains the most common industry-standard term, and we often use it in our marketing too, as do many agencies and freelancers. It’s frequently associated with A/B testing, though that’s just one test type, as previously mentioned. Businesses are drawn to CRO because it’s a clear and appealing acronym for the process of optimizing conversion rates.

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

A few years ago, while I was freelancing, we conducted an experiment on category pages by displaying the number of ‘adds to wishlist’ on product cards. Each product was unique, often with only one item available.

Highlighting popular items not only showcased the best offerings (as the page was ordered by the number of adds to wishlist/most popular items) but also instilled a sense of urgency. Revealing that e.g. over 200 people had shown interest in a specific product could spur further action. This strategy led to an increase in both add-to-cart rates and purchases compared to the base version. Despite its potential, the wishlist functionality is frequently overlooked by store owners and, consequently, by shoppers. However, it can effectively encourage customers to curate and revisit their favorite items, and, in return (in our case), that leads to better conversion rates.

In general, however, I love the simple tests: all things to do with copy, navigation, etc.

Huge thanks to Marouscha for generously sharing her expertise with us. This kind of hard-won wisdom is pure gold. To all you optimizers out there, hopefully Marouscha’s insights provided some useful food for thought as you continuously level up your skills.

We have fresh interviews dropping twice a month, so bookmark this blog and check back often. And if you missed any of our previous convos with CRO pros, now’s the time to get caught up and give these a read: 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, and our latest with Linda Bustos.