Growth

Growth Principles

Product-Market Fit (PMF)

Sean Ellis Test

Ask users: "How would you feel if you could no longer use this product?"

• Very disappointed = Must-have user
• Somewhat disappointed = Nice-to-have
• Not disappointed = Not a fit

Threshold: 40%+ "Very disappointed" = Strong PMF

###快速验证

• Can move from 7% to 40% in 2 weeks
• Focus on must-have users, ignore "somewhat disappointed"

###PMF Signals

• Users spontaneously refer others
• Retention cohorts show healthy curves
• "Ah-ha" moment is clear and repeatable

Growth Funnel

Acquisition → Activation → Retention → Referral
   (Get)      (First)      (Keep)      (Spread)

1. Acquisition

• How do users discover you?
• Channels: Organic, Paid, Referral, Partnership

2. Activation

• First-time user experience
• Key: Speed to value — get them to the "ah-ha" moment fast
• Set correct expectations before they start

3. Retention

• Do users keep coming back?
• Measure: Day 1/7/30 retention cohorts

4. Referral

• Do users tell others?
• Viral coefficient > 1 = Organic growth engine

Growth Levers

North Star Metric

Find the one metric that represents customer value:

• Notion: Weekly active contributors
• Facebook: Daily active users
• Slack: Messages sent

Test: "If we improve X, does the business grow?"

Sources

• Sean Ellis (Hacking Growth)
• Brian Balfour
• Lenny's Podcast growth episodes