Why I Started My CRO Consulting Service: Breaking the Single-Test Paradigm
After spending 11 years at trivago where all my design concepts were subject to A/B testing and seeing the company transform from a small startup into a global travel powerhouse, I noticed something critical about how most companies approach testing: they're doing it wrong.
I never set out to become a CRO consultant. My journey began as a product owner and designer, obsessing over user experiences and conversion funnels. Throughout my career, I've built several entrepreneurial ventures—co-founding Ciao (which raised $25M and was later acquired by Microsoft), building directshopper to €7M in annual revenue, and co-founding Grid with $5M in funding.
Between and alongside these entrepreneurial projects, I've consulted for dozens of businesses. In virtually every consulting engagement, I kept encountering the same critical limitation: companies were afraid to run overlapping A/B tests. My first question is always, "How many A/B tests have you run in the last month or quarter?" The answer is almost always surprisingly low.
The problem was so consistent that I started establishing the number of A/B tests as a quasi-KPI for my clients. If you're not running enough tests, you're simply not learning fast enough to compete. It doesn't matter how brilliant your team is if you're only implementing a handful of improvements per year.
The A/B Testing Roadblock I Kept Seeing
During my time at trivago, I was fortunate to witness how effective simultaneous testing could be. The founder had established experimentation as our mode of operation, and I was involved in many experiments - creating concepts, analyzing results, and implementing winning variations. I saw firsthand how this approach drove the company's growth.
This approach helped us move fast. Really fast. The mobile app I helped develop quickly became a top 10 app in Germany. We weren't just making incremental improvements—we were transforming the entire travel search experience through rapid testing and iteration.
Then I saw the same pattern repeat at Eduki, Hairskin, and inne.io: companies were waiting for one test to complete before starting another, dramatically slowing their growth potential.
What Most Companies Get Wrong About A/B Testing
While consulting for Hairskin in Switzerland, I implemented VWO testing using the overlapping approach I'd learned at trivago. I wasn't discovering something new—I was applying proven methods that most companies simply weren't using.
The conventional wisdom about isolating experiments comes from a misunderstanding of how A/B testing works. Companies think they need perfect isolation to get clean data, but this approach creates several problems:
- Painfully slow innovation cycles. If you run 1 test per month, that's only 12 potential improvements per year.
- False confidence in numbers. Even isolated tests are affected by seasonal trends, market changes, and evolving user behaviors.
- Loss of competitive advantage. While you meticulously isolate tests, your competitors could be running 5-10x more experiments.
The Overlapping Test Revolution
At inne.io, I implemented what's known in the A/B testing community as an overlapping testing methodology. Instead of waiting for one mobile test to finish before starting another, we ran multiple tests simultaneously across different user journeys.
The results were dramatic. We increased our testing velocity by 400% and identified winning variations much faster than before. This wasn't just theoretical—it translated directly to improved conversion rates.
The secret is what I learned back at trivago: randomization in A/B testing controls for the effects of other experiments. So long as you avoid tests that technically cannot overlap (like two different ranking algorithms) or that would break the user experience, you can run many experiments simultaneously.
Why I Finally Launched My Own CRO Consultancy
After implementing this approach at multiple companies—from Eduki's educational marketplace to Hairskin's e-commerce platform—I realized this knowledge gap was widespread. So in June 2024, I took the leap and established my own consultancy.
My goal wasn't just to help companies run more tests but to transform how they think about experimentation. Having raised venture funding several times in my career ($25M for Ciao and $5M for Grid), I understood the pressure businesses face to demonstrate growth. Faster testing is directly connected to faster growth.
Real Results, Real Companies
At Eduki, we established a testing process that supported their product-market fit exploration. By running overlapping tests, we could validate multiple hypotheses about their interactive worksheet product simultaneously, significantly shortening the time to achieve product-market fit.
For Hairskin, I led complex VWO implementations that went beyond the visual editor, working directly with developers to test fundamental assumptions about their conversion funnel. We didn't have to wait weeks between tests, allowing us to quickly identify winning strategies.
And at inne.io, where I'm currently consulting, we've transformed their mobile-first CRO strategy by implementing overlapping testing across both German and English markets, using a combination of VWO and GA4.
The Entrepreneurial Approach to Testing
My background as an entrepreneur—founding Ciao, directshopper, and Grid—taught me that speed matters. When you're building something new, you don't have the luxury of running one experiment at a time.
This entrepreneurial mindset is what I bring to every client engagement. Testing isn't just about optimizing a button color; it's about rapidly validating or invalidating business hypotheses to find the fastest path to growth.
My CRO Philosophy Today
After two decades in product development, and having conducted hundreds of A/B tests across multiple businesses, my approach to CRO boils down to three principles:
- Maximize testing velocity through overlapping experiments. Stop waiting for one test to finish before starting another.
- Focus on directional insights, not precision. You rarely need to know if something improved conversions by exactly 2.7%—you just need to know if it's better than what you had before.
- Build testing into your culture. Testing isn't a marketing function; it's a business improvement function that should influence every customer-facing aspect of your company.
Is Your Company Ready for a Testing Revolution?
If you're still running isolated A/B tests one after another, you're leaving growth on the table. Your competitors who have figured this out are gaining ground every day you delay.
I started this consultancy because I've seen firsthand how overlapping testing transformed companies I've worked with. It's not just about changing your testing platform or methodology; it's about changing your approach to business improvement.
After helping build multiple successful companies and products, from Ciao's growth and acquisition by Microsoft to trivago's mobile app success, I'm now focused on helping businesses accelerate their growth through smart, fast, overlapping testing strategies.
The old way of A/B testing is holding you back. Let's fix that.