When I joined my first role at Squarespace as a Data Scientist embedded in the Growth team, I had to do a little research as to what exactly "Growth" was. Fast forward a year and change later, and not only am I more confident about growth concepts, but it's what I do and think about on a daily basis.

One of the books that came up most frequently when I was poking around was Hacking Growth. Sean Ellis and Morgan Brown break down a systematic way of collecting, analyzing, and testing data so that businesses can make the most of their time and resources later coined "growth hacking," both for better and worse.

It took a little longer than expected, but I finally made my way through the book and I'm here to share my favorite takeaways and notes.

Team Makeup and Process

  • The team that pushes code the most frequently generally wins.
  • The growth skillset is centered around a few traits: Fluency in data analysis, product management, and experiment design.
  • Strong growth leads provide air cover for the team to experiment without constant pressure from management to deliver wins.
  • Growth hacking is a continuous process from data analysis to idea generation to experiment prioritization to running the experiments.
  • Sprint planning meetings are for reviewing progress, prioritizing experiments, and maintaining experiment velocity over time.
  • Growth teams are responsible for "invalidating lore" about products and markets.
  • Cross-functional collaboration and sharing of information are table stakes.
Growth teams help to keep companies on their toes, constantly on the lookout for changes in customer behavior and experimenting with new ideas for growth. Growth teams are both active and proactive; they are detectors of early warning signs, and they are entirely dedicated to acquiring, activating, retaining, and monetizing the maximum number of customers and even driving the innovation of new opportunities for growth.

Running Experiments

  • Produce dramatic lifts early on. When your customer base grows, then you can shift to experimenting in more niche areas.
  • A good plan executed today beats a perfect plan tomorrow.
  • Big successes in growth hacking come from a series of small wins, compounded over time.
  • Don't move into high-tempo growth experimentation until you know your core value, to which customers, and why.
  • Even failed experiments can lead to significant learning over an incredibly short time frame.
  • The best way to have good ideas is to have lots of ideas.
  • Periodically shift focus to the next stage of the customer funnel: From acquisition to activation to retention.
  • Before you move on to a new initiative, make sure you have exhausted experiments for channels and tactics that have proven successful.
After this renewed push, we have settled into a steady and vigorous — if somewhat less intense — testing schedule most of the time, with periods of more rapid tempo when launching new initiatives, such as new software or a new marketing test. Such ebb and flow is to be expected, but the key is to stay on top of growth metrics rigorously, and to constantly ask if the team is slowing down for a valid reason, or if complacency is creeping in. If it’s the latter, the team needs to pick up the experimentation pace immediately.

More Tactical Advice

  • Love creates growth, not the other way around. And for there to be love, you need an aha moment.
  • Your North Star should be the metric that most accurately captures the core value you create for customers.
  • Customer acquisition cost is not a preordained formula. It's a function of many variables specific to the company's business model, competitive situation, and stage of growth.
  • Most businesses get zero distribution channels to work. It's likely that one channel is optimal.
  • Poor distribution, not product, is the number one cause of failure.
  • When instrumenting virality, make the experience of sharing as user-friendly and delightful as possible.
  • If users don't love it, they aren't going to share it. Virality is a balance of how good the packaging is and how good the content is.
The first phase of work in scaling up your acquisition of customers should be devoted to achieving two additional types of fit: language/market fit, which is how well the way you describe the benefits of your product resonates with your target audience, and channel/product fit, which describes how effective the marketing channels are that you’ve selected to reach your intended audience with your product, such as paid search advertising or viral, or content, marketing.

Parting Thoughts

It's only right that I call out how little of the book these notes actually cover. By the time I got around to Hacking Growth, a lot of the concepts that I came across where already cemented in my head from lots similarly inspired online resources.

What you just read above were the ideas that I found particularly interesting. I hope they were interesting to you as well.  

If you enjoyed this and are looking for more like it, check out my guide to onboarding and The Lean Startup, another classic that has a good amount of overlap with the notes above. Besides, for growth nerds like me, I think that a little repetition is worthwhile for material this foundational.


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