Medium and Substack · Metrics · Mid · 45 to 60 minutes

How should Medium measure product value?

Medium is an online publishing platform for writers and readers, and Substack is a newsletter platform where writers own their audience and can charge readers directly. Answer this product management case and get it graded line by line against a weighted rubric.

Metrics design
Product strategy
Trade-off analysis
Customer insight
Written communication

The situation

You are a PM at Medium during its early growth. The Head of Product asks you to recommend how the company should measure product success for article reading and discovery. Medium's mission is to be the easiest way for anyone to publish online, and discovery is central because many writers arrive without an audience. Leadership wants a simple way to align teams as they improve recommendations on article pages and consider future monetization paths. Some teammates want one clear usage metric, such as reading time, because it is easy to track and can speed up decisions. Others worry that if Medium optimizes too hard for attention, it may improve short term engagement while weakening the experience for writers, readers, or both. You need to propose a metrics approach that can guide product choices in this area, especially around discovery, without losing sight of customer value. This is hard because Medium is a two sided product, the needs of writers and readers are not identical, and the easiest signals to measure may not reflect why people choose Medium in the first place.

What to produce

Write a 1 to 2 page product strategy memo.

Your answer must

State the core decision and identify whose value should anchor the product area when writer and reader goals conflict.
Propose a metrics framework for article discovery, including either one primary metric with guardrails or a clear case for not using a single North Star.
Explain how your framework stays tied to customer value rather than only on site engagement.
Describe how you would evaluate discovery changes using both product analytics and direct customer input.
Name 2 to 3 likely failure modes from choosing the wrong metric and how you would detect them early.

Constraints

Keep Medium's mission, making publishing easy for anyone, at the center of your recommendation.
Do not remove discovery entirely, unknown writers still need a way to reach readers.
Do not assume a new business model or large research team, your approach should be feasible for a growing product team.

Format

A strong memo uses sections like objective, customer value, metric framework, decision rules, validation plan, and risks.

How Medium and Substack actually played it

Compares Medium's time spent reading metric with Substack's focus on writer needs and revenue. It argues that engagement metrics can drift away from customer value.

An engagement metric can reward the wrong behaviour
Anchor metrics to customer value
Mix usage data with direct customer priorities

Built from North Star Seduction: Why Startups Are Shunning Metrics-Led Product Strategies by Daniel Kyne (OpinionX).