Atlas: You're a Head of Growth at a startup. You've just launched. The pressure is on. Your board is asking about user numbers, your team is looking for direction. What's the one thing you should focus on right now to guarantee success? Most people get this wrong. They chase users, they build viral features, and they burn through cash, only to watch their product fizzle out. They build a growth engine for a car with no wheels.

Susan: That's a feeling I know all too well. It's the central tension of any early-stage company. The pull to scale versus the need to build something that actually works.

Atlas: Exactly. And in 'Hacking Growth,' Sean Ellis argues that this is the single biggest mistake a startup can make. Today, we're going to tackle this from two critical perspectives. First, we'll explore the absolute prerequisite for any growth strategy: creating a 'must-have' product that users genuinely love. Then, we'll discuss how to find your 'North Star Metric'—the one number that truly tells you if you're succeeding and guides every decision you make. I'm your host, Atlas, and I'm thrilled to have Susan, Head of Growth at a fast-moving edtech startup, here with us. Susan, welcome.

Susan: Thanks for having me, Atlas. This is the core of what I think about every day, so I'm excited to dive in.

Atlas: So, Susan, let's start with that first, critical question. The book argues that before you even think about growth, you need a 'must-have' product. What does that even mean? Let's look at a company that learned this the hard way: BranchOut.

Susan: Oh, I remember them. A flash in the pan.

Atlas: A huge flash. Back in 2010, they wanted to be the professional network on Facebook, basically to kill LinkedIn. They needed to grow fast, so they built this incredibly clever viral hack. It let users bypass Facebook's 50-invite limit, so people could spam their entire friend list. And it worked, at least on paper. They exploded from four million to twenty-five million users in just three months.

Susan: Those are numbers that would get any investor excited.

Atlas: Absolutely. But here was the problem. When those new users arrived, the app was a ghost town. It was an empty experience. There was no 'there' there. The product didn't actually do anything valuable. So, users were massively disappointed, and the churn was astronomical. Despite raising nearly 50 million dollars, the company was eventually sold for a tiny fraction of that. They built a phenomenal growth engine, but for a product nobody wanted.

Susan: That's fascinating and terrifying. It's the ultimate vanity metric trap. In edtech, we see a parallel. You can get a million sign-ups for a new learning app, but if students don't actually learn something, if they don't have that 'aha moment' where a concept finally clicks, they'll never come back. The 'must-have' quality isn't the download; it's the educational outcome.

Atlas: You've hit the nail on the head. The book calls that the 'aha moment.' And it contrasts BranchOut's failure with the success of Yelp. When Yelp first launched, it wasn't a review site. It was a more complicated service. But the founders noticed something in their data. A small group of users were organically using a buried, almost hidden feature to write reviews of local businesses.

Susan: So they were finding the value themselves, without being prompted.

Atlas: Exactly. That was the 'aha moment'—finding a trusted, real-person review for a local spot. So, they pivoted. They threw out their old plans and rebuilt the entire company around that one must-have feature. And we all know how that turned out.

Susan: So the key success factor for a launch isn't the launch plan itself, it's validating that 'aha moment' first. It's about finding that one thing that users are desperate for, even if it's not what you originally intended to build. Which leads to a practical question: how do you even measure that early on? Before you have massive data sets?

Atlas: That is the million-dollar question. And it's the perfect transition to our next topic.

Atlas: Because once you know what your 'aha moment' is, you need a way to measure if you're delivering it. This is where the book's concept of the 'North Star Metric' comes in. It's not about traffic or downloads; it's about measuring the delivery of core value.

Susan: This is so important. It's easy to get lost in a sea of data. A single, guiding metric feels like a lifeline.

Atlas: It is. And the book uses a brilliant comparison to explain it: Airbnb versus LinkedIn. Both are huge, successful platforms, but a good North Star for one would be a terrible metric for the other. For Airbnb, what's the core value they deliver?

Susan: A successful stay. A great travel experience.

Atlas: Right. So their North Star is 'nights booked.' That single number tells them if both hosts and guests are getting value. Measuring 'daily active users' would be pointless. People don't book vacations every day. But now think about LinkedIn. What's their core value, especially for their paying customers, the recruiters?

Susan: It's the size and quality of the talent pool. They need a massive database of professionals to search through.

Atlas: Precisely. So for LinkedIn, a metric like 'total profiles created' is actually a fantastic North Star. Even if a user only updates their profile once a year, their presence adds value to the network for recruiters. It's a completely different model.

Susan: That's a brilliant distinction. It forces you to define your business model and who you're creating value for. For my edtech startup, if our 'aha moment' is a student mastering a new skill, then our North Star can't just be 'time spent in app.' That could mean they're confused. It might be something like 'number of skills successfully passed per week' or 'number of students forming active study groups.' It has to tie directly to the learning outcome.

Atlas: You're thinking exactly like a growth hacker. The book gives another great example with WhatsApp. Their North Star isn't daily active users, it's 'number of messages sent.' Because that's the core value. Someone can be active every day but send one message—they aren't a core user. Someone who sends 50 messages is deeply engaged.

Susan: Right. It's about measuring engagement with the core value proposition. That clarifies so much. It moves the conversation from 'how many users do we have?' to 'how much value are we delivering?' It's a fundamental shift in perspective that's critical for an early-stage product. You can't afford to measure the wrong thing.

Atlas: And if you measure the right thing, it focuses the entire team. Every experiment, every feature, every marketing campaign can be judged against a single question: will this move our North Star?

Susan: That's the kind of clarity a startup needs to survive.

Atlas: So, to bring it all together, the book's answer to your launch questions is a powerful one-two punch. First, obsess over creating a 'must-have' product by identifying and delivering that 'aha moment.' Don't even think about scaling until you've nailed this.

Susan: And the BranchOut story is the perfect warning of what happens if you get that order wrong.

Atlas: Second, define a North Star Metric that measures the delivery of that core value, not just noise. It's your compass that keeps the entire company pointed in the right direction.

Susan: Exactly. And for anyone in my shoes, listening to this and wondering where to even begin, the book offers a very concrete first step which I find incredibly useful. It's called the 'Must-Have Survey.'

Atlas: Break it down for us.

Susan: It's beautifully simple. You just ask your early users one question: 'How would you feel if you could no longer use this product?' The options are 'Very disappointed,' 'Somewhat disappointed,' or 'Not disappointed.'

Atlas: And what's the magic number?

Susan: The book says if you don't get at least 40% of your users saying they'd be 'Very disappointed,' you don't have a must-have product yet. And you shouldn't be focused on growth. You should be focused on fixing the product. That's the real starting line.

Atlas: A simple, powerful, and potentially brutal diagnostic tool.

Susan: It is. But it's the truth you need to hear before you start spending money to acquire users who won't stick around. It's about building on rock, not on sand.

Atlas: A perfect place to end. Susan, thank you for bringing your real-world expertise to this. It's been incredibly insightful.

Susan: My pleasure, Atlas. This was a great conversation.