Smarter Techies

Smarter Techies

Share this post

Smarter Techies
Smarter Techies
Don’t Waste Time Applying to FAANG Without Knowing These Metrics

Don’t Waste Time Applying to FAANG Without Knowing These Metrics

Your crash course in product metrics

Mandy Liu's avatar
Mandy Liu
Dec 06, 2024
∙ Paid
14

Share this post

Smarter Techies
Smarter Techies
Don’t Waste Time Applying to FAANG Without Knowing These Metrics
4
2
Share

Why do product companies obsess over metrics?

Simple: You can’t improve what you don’t measure.

Peter Drucker nailed it with that line.

Metrics are the lifeblood of product-centric companies. The bigger a company gets, the more metrics become the glue that aligns everyone—data scientists, product managers, engineers—toward a common goal.

Without them, it’s like driving blindfolded.

If you’re aiming for a career at a product-focused company (or leveling up where you are), mastering metrics isn’t optional—it’s your ticket to the table.

Who needs to know this?

  • Data scientists and analysts: If you can measure impact, you can drive impact.

  • Product managers and engineers: Metrics translate fuzzy product ideas into actionable strategies.

  • Aspiring product professionals: Dreaming of FAANG or similar companies? Metrics will make or break your interviews.

What you’ll learn here:

1️⃣ The 3 essential metric types

Ever been asked in an interview, “How would you measure the health of Facebook Groups?” Learn the framework companies use to assess this.

2️⃣ How to choose the right metrics

3️⃣ Examples of common metrics

Engagement, retention, growth—they all tell a story. Learn how to read and leverage them, and excel in interviews

orange carrot on blue surface

3 metrics every FAANG applicant should master

1. The north star: your compass

What: A single metric the team/company uses as a measure of success.

How to pick:

  • Timely

  • Specific

  • Easy to grasp

  • Captures long-term goal

Example: Facebook’s north star is monthly active users (MAU)

2. Secondary metrics: the sidekicks

What: The supporting cast. They dive deeper into specific areas that influence the north star.

How to pick:

  • Granular insights

  • Leading indicators

  • Help teams track progress and tweak strategies before it’s too late.

Example: For Facebook, new user acquisition might be a secondary metric. It’s a key driver of MAUs but doesn’t tell the full story.

3. Counter metric/guardrails: your safety net

What: Ensure things don’t go sideways while chasing growth. They’re like a reality check to prevent unintended consequences or quality drops.

How to pick:

  • Can reflect bottom line

  • Can reflect customer satisfaction

Example: Cancellation rate. If acquisition is booming but cancellation rates skyrocket, it signals trouble.


Now, let’s make it real with an everyday example: losing 10kg

Imagine you’re on a mission to shed 10kg.

  • North star: Your weight. It’s the ultimate goal but takes time to reflect changes.

  • Secondary metrics: Calories consumed daily or workouts completed weekly. These track the activities that lead to weight loss.

  • Guardrail: Your mood. If your daily energy or happiness dips too low, it’s a sign you’re overdoing it.

A tech example: launching YouTube Shorts

Imagine YouTube launching Shorts to rival TikTok.

  • North star: Daily Active Users (DAU) on Shorts.

  • Secondary metrics: Minutes watched and Shorts created per day.

  • Guardrail: YouTube ads revenue. Shorts might cannibalize longer videos, where ads generate most of the revenue.

Got it?

Good.

Now that you understand the 3 types of metrics, here’s the fun part: learning how to apply them.

Next, we’ll dive into the most common metrics FAANG companies use, and how to stand out in interviews.


First, north star metrics

Here’s a nifty breakdown of north stars by business model:

This post is for paid subscribers

Already a paid subscriber? Sign in
© 2025 Mandy Liu
Privacy ∙ Terms ∙ Collection notice
Start writingGet the app
Substack is the home for great culture

Share