Xavier Fok

A plain-English look at how to identify discount-only buyers, measure their retention and CLV, and test whether they’d stick around without the coupon.

A plain-English look at how ai spreadsheet analysis actually works, what a language model can tell you about your churn and MRR numbers, and where it quietly gets things wrong.

A practical UTM naming convention for solo operators, so six months from now your campaign reports still tell you something true.

A plain-English guide to reporting revenue across multiple currencies without letting exchange rate noise disguise itself as real growth or decline.

Monthly churn math falls apart on annual plans. Here’s how to actually track renewal risk and customer loss when your customers only bill once a year.

A plain English look at the novelty effect in product testing: why new features spike on launch, how to tell a real lift from curiosity, and how to run novelty effect testing without fooling yourself.

How to catch a sample ratio mismatch before it quietly ruins an A/B test, and what to do about it once you find one.

Consent banners don’t just protect privacy, they quietly reshape your analytics. Here’s what actually happens to your data when visitors click accept, reject, or nothing at all.

Open rate used to tell you whether people read your emails. A change in how Apple Mail loads images broke that, and most senders never adjusted. Here’s the mechanism, and what to track instead.

A solo operator’s honest review of a year spent tracking churn, MRR, CLV, and conversion by hand, and what actually changed in how I read my own numbers.