Product-Led Growth:
How Slack Learned to Scale

Merci Grace

Founder, Investor, Former Head of Growth at Slack

LENNY'S PODCAST

The Core

What Slack Discovered About Work Tools

"There was an internal campaign demanding we allow people to block each other on Slack. But blocking is a work tool, not just a safety tool, it can exclude people from meetings, tank their performance. Slack is a work product first."

Slack is fundamentally a work tool, not a social network
This clarity made thousands of small decisions instant and obvious
Every feature question comes back to: does this serve work?
Stewart & early team embedded this DNA so deeply that it guided everyone who followed

The Method

Building Product-Led Growth from First Principles

Start with game design: The onboarding mindset Merci brought, how do you introduce someone to a world they've never seen?
Curiosity first: Don't assume you know what matters. Let data surprise you. April Underwood's line: "No one has built Slack before."
Copy nothing: Watch competitors copy your failed experiments and wonder why they're not working. Your onboarding solves YOUR product.
Speed over perfection: Test fast. Iterate on real humans. Kill bad experiments immediately.

The earliest focusNot called "growth." Called "new user experience", onboarding, signup, getting started. Product-first thinking.

The mental modelStart with onboarding in your product design, not at the end. If you haven't thought about how someone enters the world, the product isn't done.

The Practice

Onboarding: The Hardest Growth Lever

Don't preach: No carousel with "7 things you must know." Users won't read it. They don't care about your product the way you do.
Let the product teach: A to-do list app with "Click here to complete your first task", that's onboarding. It's part of using the product, not apart from it.
Talk to humans: Once a month, watch someone sign up for your product cold. See their face. Hear their frustration. It's messy and uncomfortable and absolutely necessary.
Don't copy templates: "Replicate Slack's onboarding" doesn't work. It has to be native to YOUR product, YOUR value, YOUR experience.

The trial length myth

People think a 7-day trial rushes them to buy. But buying has nothing to do with your schedule. It's about their quarter, their budget, their new project. Give people more time, they convert incrementally more.

The attention problem

Most onboarding fails because the designer didn't think about it early enough. By then the product is done. Start designing from the onboarding forward.

Playbook

Go Product-Led

Obsess about the first 10 minutes. That's where your growth lives.
When in doubt, simplify. If your onboarding doesn't feel dumbed down, it's too complex.
Invite flows work because people want to share. Give them the option, step out of the way, let them decide.
Never assume users are as invested in your product as you are. Design for apathy.

Merci's convictionProduct-led growth isn't cheaper than sales. It's a different product strategy that only works if you design the product FOR growth from day one.

Contrarian

Common Product-Led Growth Myths

✗Onboarding is a final polishINSTEAD →✓ Onboarding IS the product strategy. Design it first or watch your growth die.

✗Carousels are good UXINSTEAD →✓ Carousels are dismissal screens. Unless the product IS a carousel (Tinder), they fail silently.

✗Copy Slack's playbookINSTEAD →✓ What worked for Slack works for no one else. Build onboarding native to your product's value.

✗Shorter trials = faster conversionsINSTEAD →✓ Longer trials convert incrementally better because buying has nothing to do with your timeline.

Based on Merci Grace's episode on Lenny's Podcast. All ideas on this page are from the episode.Read the episode on Lenny’s Newsletter

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