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New to product: Build foundations · Core

Learn the numbers product managers use

PMs use a small set of numbers to see whether a product works: how many people try it, how many stay and whether a change made a difference. You do not need to be a data scientist, but you do need to read numbers well.

About 3-5 daysEvergreenLast reviewed 9 November 2026

Who this applies to

Skills it builds
Data and measurement
PM types
All
Product types
All
Starting points
Exploring product management
Ways of working
All
Experience
Beginner (under 1 year)
Size of organisation
All

Steps

  1. Learn four ideas: a funnel (how many people complete each step), retention (how many come back), a north star metric (the one number that shows value) and an experiment (comparing two versions). Write one example of each from a product you know.
  2. Read the funnel analysis guide. Sketch a funnel for signing up to a service you use, mark where you think people drop off and say why.
  3. Read how a retention analysis is built. Describe how you would check whether people were still using a new feature a month later.
  4. Read about north star metrics. Write one for a product you know, then list two other measures that would warn you if chasing it caused harm.
  5. Read an introduction to controlled experiments. Note what makes a result trustworthy: a clear hypothesis, enough users, a long enough run and one change at a time.
  6. If you want to go further, spend an hour on the interactive SQL lessons in the sources. Understanding how to ask a database a question helps with every conversation with analysts.
  7. Take one chart or statistic from a news story and list the questions you would ask before trusting it.

Tool examples

Google Docs
Keep a one-page glossary of the terms with an example for each.
Claude
Ask it to explain one measure with a made-up example, then check the explanation against a source.

Definition of done

  • One example of each of the four ideas
  • A sketched funnel with guessed drop-offs
  • A list of questions for one chart

Common pitfalls

  • Chasing a single number without checking side effects
  • Reading small changes in small samples as proof
  • Skipping the basics to jump straight to dashboards

Do these first

Sources