“If you haven't read Lean Analytics by Alistair Croll and Ben Yoskovitz, stop reading this blog post and go pick up a copy. No really. It's that good. For those of you who didn't stop reading to go buy the book, I'll work on convincing you.”
Teresa Torres argues that many teams run A/B tests without first knowing what they are trying to learn, which produces wasted effort and unclear results. Before testing, a team should define a specific hypothesis and…
Teresa Torres argues that product leaders need only a basic grasp of statistics to avoid being misled by A/B tests. She explains statistical significance using a conversion example and warns that many web testing tools…
Marty Cagan argues that many product teams still fly blind because they do not instrument their products to collect usage analytics, or collect so little that they cannot see how customers actually use features. He…
Teresa Torres recounts advising a junior designer who wanted to grow in user experience design. She argues that hands-on learning matters more than reading or talking, and that the designer's best growth opportunity is…
Lenny answers a reader question by unpacking how Airbnb built a strong experimentation culture, using its early data science hires, north-star metric, embedded data scientists, and trustworthy tooling as the core story…
Torres argues that all-time totals, like lifetime registered users, are rarely useful because they only go up and hide whether a product is improving or declining. The right measure depends on choosing a time increment…
Aman Khan argues that writing evaluations is becoming a defining skill for AI product managers, since evals measure how each part of a system affects quality. The post explains what evals are, compares human, code-based…
Lenny Rachitsky lays out the four metrics he considers most important for an early marketplace: fill rate, bookings growth, supply growth, and GMV growth. He explains why each matters, shares practitioner perspectives…
Lenny Rachitsky shares advice, drawn from researcher Matt Gallivan, on which questions to ask users to judge product-market fit. He recommends a survey for 100+ active users and interviews for smaller bases, while…
Teresa Torres argues that discovery teams should be judged by whether their discovery work actually moves a desired product outcome, tracked as absolute progress quarter over quarter rather than percent of a goal. Since…
Teresa Torres recounts how her team at AfterCollege nearly celebrated a false win: a report claimed their new Explore feature beat the old Search, but the funnel had been misread as page-to-page when it was actually a…
Teresa Torres argues that A/B testing should follow the scientific method rather than being used for trivial tweaks like button colors or wording. She recommends starting from a real insight about why recipients ignore…
Marty Cagan argues that product teams often fixate on a single kind of analytics, usually web analytics, and miss the larger picture. He lays out four flavors that matter for product work: user analytics on how real…
Torres argues that teams should stop testing ideas at random and instead be strategic about what they experiment on. Rather than prioritizing a list of ideas by gut feel, teams should estimate expected outcomes…
Teresa Torres argues that many product managers run experiments poorly: they struggle to choose what to test, decide how long to run tests, lack scientific training, find tools hard to use, and overgeneralize results…
Teresa Torres argues that product teams should test ideas with experiments before building them, and that this starts with a well-formed hypothesis. Vague statements like 'a redesign will improve usability' cannot be…
Guest authors Michael Kaminsky and Mike Taylor explain how marketers measure incrementality, the true sales caused by spend, using three methods: multi-touch attribution, marketing mix modeling, and conversion lift…
Cagan argues that many companies lack a clear way to tell whether product managers' work actually aligns with business strategy, and that teams drift into chasing feature ideas. He proposes a 'Product Scorecard': a…
John Cutler examines the sudden enthusiasm for measuring "return on tokens" as AI usage grows inside companies. He argues that vendors and executives eager for clean numbers are reaching for yet another proxy, much like…
In this podcast episode, host Teresa Torres and guest Petra Wille examine whether every product outcome must be measurable. Torres revisits her long-held view that outcomes should always be metrics and explains why she…
This paid post explains how to measure retention using cohort analysis, including how to read cohort charts for trends and for signs of flattening that indicate product-market fit. It then previews a framework of seven…