How Experimental Evidence Travels Through Your Organization: Why Better May Be Worse

How Experimental Evidence Travels Through Your Organization: Why Better May Be Worse
Sebastian Ankargren, Senior Data Scientist
Sebastian Ankargren, Senior Data Scientist

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It's well established that an organization's success with experimentation depends on culture. Tools and platforms make up the foundation, but they only add value if the culture lets people use them effectively.

This post explains what separates an organization that merely experiments from one that makes better product decisions through experimentation. No matter how sophisticated an experiment is, it's useless unless product teams can translate its results into action.

Ideas turn into evidence through experimentation

Imagine you're the product manager for a search feature. Users say it's hard to find items. You propose a two-step search. Later, you test this idea in an A/B test. The results carry some value as evidence: if your organization trusts and acts on them, the value is high. If not, the value of the evidence is low and it has little impact.

A strong experimentation culture raises the weight given to experimental results in decision-making. The better an organization handles each step—from idea to evidence—the more potential value it realizes.

The evolution of an idea

The evolution of an idea

Here's how an idea evolves:

  1. The idea becomes a testable hypothesis.
  2. The hypothesis is implemented as a change.
  3. The change runs in an experiment, producing an analysis.
  4. The analysis informs a product decision.

Each phase passes value forward—or loses some along the way. The goal is to realize as much of the idea's original potential learning value as possible. Even learning that something doesn't work can be valuable if it's done well.

From idea to hypothesis

Turning an idea into a clear hypothesis determines how much value survives. An idea like "users will appreciate a new design" becomes weak evidence if tested as "a 90s-style redesign will increase conversion by 5%." The hypothesis is too narrow to capture the idea's potential.

This hand-off lies in the product and design domain: defining what to test and why. Hypotheses that are timid or poorly scoped limit what experiments can teach. Bold, clear hypotheses preserve more value.

From hypothesis to change

When the hypothesis is set, engineering turns it into a working change. Even good hypotheses can lose value here through flawed implementations.

Imagine the two-step search is built but introduces latency. Any preference users show may reflect slower load times, not the search design. The value of the evidence collapses.

Similarly, issues like sample ratio mismatch or unintended side effects can obscure results. The engineering task is to implement cleanly—capturing only what the hypothesis intends.

From change to analysis

With data collected, the next step is to analyze results. Analyses range from automated reports to complex statistical modeling. Poor data quality, irrelevant metrics, or confusing presentations can all destroy value.

Data engineers ensure correct inputs; data scientists translate results into insights. Modern platforms automate much of this, freeing data scientists to define metrics, templates, and guidelines that maintain consistency.

The analysis must not only be technically correct but also understandable and trusted. If stakeholders doubt or misinterpret it, the value of the evidence drops regardless of rigor.

From analysis to decision

When the experiment concludes, decision-makers must act: ship, scrap, or iterate. They weigh the analysis alongside other inputs—user research, strategy, and intuition.

Crucially, the same idea can yield very different impacts depending on how much value survives through each phase. Sometimes, a simpler analysis drives more impact than a sophisticated one, simply because stakeholders understand it better.

Why better may be worse

After years of experimentation at Spotify, one clear pattern emerges: success comes from doing the basics well and at scale. Complexity increases the risk of value loss. Sophisticated changes or analyses can fail because they're hard to implement or interpret.

For example, a technically advanced statistical method might be theoretically optimal, but if stakeholders don't understand it, they'll rate the evidence as low. A simpler, familiar analysis may have greater influence on decisions.

The lesson: tailor your experimentation process to your organization's level of statistical fluency and decision culture. If teams value advanced methods, use them. If they're still building comfort, focus on making standard analyses robust, consistent, and clear. Standardized reporting can often deliver more value than introducing complexity.

Potential impact of infrastructure on strength of evidence

Infrastructure decisions, like adding new platform features or statistical methods, should be evaluated by their impact on the strength of the evidence produced, or on velocity, and not on theoretical sophistication. A common fallacy is to assume every "better" local change (for example, a more complex model or new platform option) improves outcomes. In practice, more features can create friction and confusion, reducing overall value.

As an example, Spotify makes heavy use of various types of bandit algorithms in personalization, but so far never in experimentation. Supporting them would give experimenters more choices—but also more chances to choose poorly. The extra complexity could lower the value of the evidence, not raise it.

Every platform feature introduces two possible worlds: one with it and one without. Unless the new world clearly increases the quantity or quality of usable evidence, it's not an improvement.

Conclusion

To succeed with experimentation, optimize for the strength of the evidence produced and its product impact, not for theoretical perfection.

  • Don't locally optimize one phase (like using the "best" statistical test) without checking if it improves end-to-end outcomes.
  • Simplicity often wins: complex choices introduce risk and confusion.
  • Avoid vanity features that add flexibility but erode confidence.
  • Remember scale: the power of experimentation lies in running many clean, reliable tests—not a few intricate ones.

Hand-crafted analyses and one-off deep dives are vital for discovery, but it's through consistent, scaled execution that experimentation transforms how an organization makes decisions.