As Co-Founder of the hyper-local social network, Nextdoor, I’m often asked about the early days and how we came up with the idea. Was it like a bolt of lightning that struck unexpectedly, or the result of many failed attempts? When I’m talking with fellow entrepreneurs, they often ask a more pointed question: “How did you find product-market fit?”

Savvy entrepreneurs know that finding product-market fit is essential for building a successful business. I like to think of product market fit (PMF) as the unique product solution that addresses a missing gap in the market. The most attractive markets are large and hard for others to enter, creating an opportunity to build a meaningful and defensible business. The hardest part is finding the “fit” in a previously hard-to-solve space, but that's where the greatest business opportunities are found.

While the “idea” and the product-market fit (PMF) for Nextdoor are not precisely the same, they both were shaped by the struggle to find product-market fit at Fanbase, an earlier company I co-founded. Fanbase’s failure led to a hard pivot and our team’s search for a better way of launching products. It was a two-year journey of frustration, but the lessons we learned eventually paved the way for the successful launch of Nextdoor.

While each startup's journey is unique, I believe the PMF journey can broadly be broken down into five steps. The sequence matters, or you’ll find yourself doubling back again and again. Taking these steps early to validate the market appetite for your product can dramatically increase your odds of success.

Here are the five steps that can help you build a transformative product for the market: ‍

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1. Validate your hypothesis

To start on the entrepreneurial journey, you need to have a unique insight about the market. Where is the gap? Put it into words. Force yourself to write it down. What has to be true for the market to want what you need? A good hypothesis should include the following:

• Who is the target customer?
• What is the unmet need?
• Why aren’t their needs being met today?

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For Nextdoor, we believed that neighbors had lost touch with each other and wanted a more convenient way to connect with each other about what was happening in their neighborhood.

Key takeaway: Writing down assumptions allows for clarity with yourself, your co-founders, and teammates. It’s important to write your hypothesis with clear who, what, and why statements. What’s the benefit for your target users? Follow-up by sharing your hypothesis with others and get their feedback. The feedback you’ll get is worth way more than the risk of someone stealing the idea.

2. Test product assumptions with users

It’s so easy to get excited about an idea and want to just start building. You may feel competitive pressure or assume the market opportunity is fleeting. But that would be a mistake. As my PartnerAndy Johns likes to say,

“It’s not first to market, but first to product-market fit that matters.”

First, you should test your product assumptions with users and validate if your proposed product resonates with users. Be humble enough to know that your product assumptions are not 100% right and that the smart move is testing your proposed solutions before you dive into building.

These tests should be fast and cheap. You should be able to change directions within days, if not hours. Some example tests methods include:

• surveys
• paper mock-ups
• “Wizard of Oz” tests
• 1:1 interviews

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Never outsource the work or short-change the face-to-face interactions with customers. The personal interactions with customers are where the golden insights lie. I did nearly 100 interviews and 1:1 sessions with our early users at Nextdoor. Those meetings provided an endless number of product and Go-To-Market insights. Understand who likes your product and why. Where is the “Aha” moment where users get excited and can’t wait to use your product? Look for strong and clear signals. The most actionable feedback will not be subtle.

At Nextdoor, we spent about six weeks doing online surveys, meeting with neighborhood leaders, and showing people crude wire-frames and mock-ups. Based on those interviews, we materially changed the focus of the product and narrowed the scope to the most essential features. This saved us months, if not years, of wasted work. It also helped us understand who the true believers and early champions of Nextdoor were going to be. These people were critical in building the Nextdoor community. When people saw the neighborhood map and understood who was on the network, there was a clear “Aha” moment and the whole concept came together for them.

Key takeaways: Spending extra time refining the idea with a small group of invested users will save you months of work. It can also lead to moments of insight based on user frustrations and hard-to-articulate needs that are more easily understood face-to-face. These insights often inspire nuanced solutions that can differentiate your product from others. It will also help you identify your true diehard users who will be the foundation of your business.

3. Prototype your MVP in the real world  

After weeks of high-touch research, resist the urge to start building the full-feature solution. You might have some good feedback, but you are still developing your concept. Instead, focus on validating your proposed product solution in more realistic market conditions by building a simple prototype. You'll iterate on it before you get it right, but you need the minimum viable product (MVP) to test your assumptions and continue learning. The goal is to get answers to a few key questions about the product before you decide to build a company around it. Often founders mistake the “Viable” in MVP as meaning the easiest version of the product for the engineers to build. Rather, the goal is to create the minimum product that sparks delight with users. MVP should really stand for Minimum Valuable Product. Why should the users care if there isn’t something delightful about it?

For Nextdoor, we built a simple prototype for one neighborhood to test the likelihood of neighbors to converse with each other. We stripped away functionality and tested one hypothesis at a time. At first, we just wanted to see if neighbors would have anything to talk about if we brought them together online. That first prototype we built was embarrassingly crude, but after only four weeks we had a working prototype. Within a few weeks of release in our test neighborhood, we knew that neighbors had a lot to say and share with each other. We then tested how neighbors would invite one another. From there, we moved on to test how they wanted to define their neighborhood. Once we tested those questions with one neighborhood, we expanded to five more neighborhoods and validated the initial feedback and the market potential.  

We continued this prototype and learning process for several months as we added a few new neighborhoods each week. We made a point of launching these neighborhoods across the country to get a broad set of feedback. I knew we were finding product-market fit one day when we had about twenty neighborhoods and took the service down for an hour to upgrade a database in the middle of the day. Within 10 minutes, I started getting emails and phone calls from concerned users who were unable to access the service. They needed Nextdoor—now!

At Nextdoor, we used user testing and customer support feedback to calibrate member delight and product-market fit. Over the years, people like growth leader Sean Ellis, have developed a simple survey designed to measure and track an objective score to measure and track product-market fit. I wish we had used something like this to calibrate our progress during this testing phase. It probably would have saved us time.

Key takeaways: There is no substitute for real people using your product in real life scenarios. The key is to quickly prototype a MVP to validate your product assumptions and confirm user delight. Don’t throw more engineers at the problem. Instead, limit the scope to answering the 1-3 essential questions. If you have multiple questions to answer, isolate each variable and test them sequentially. In this area, I believe small, nimble teams have a big advantage—constraints force trade-offs and drive innovation faster. Find a way for the team to track progress with some objective measures. It will help keep the team aligned and motivated.

4. Codify your detailed personas

Just as products need in-market testing, I believe we must also test user segmentation and messaging. Fortunately, this usually can happen in parallel while the engineering team is building the initial product.

For Nextdoor, the marketing team went to work testing messaging through surveys, interviews, and digital campaigns. Luckily, we also collected a lot of information about our Founding Members, the first users who started their own Nextdoor neighborhood and invited their fellow neighbors to join. As part of the product sign-up flow, we required each Founding Member to complete an application about why they wanted to start their own neighborhood. That information helped us understand our earliest users and develop our personas. It was an essential way to align our growing team and be precise about who we were targeting in the early days.

These personas guided our product strategy, helped us build the roadmap, develop marketing messages, prioritize partnerships, and optimize sign-up flows. Most importantly, it empowered everyone in the company to prioritize and say no to work that didn’t directly help our selected personas be successful on Nextdoor. Avoid trying to please everyone with too many personas. Personas are another way of saying: "Here are all of the people that we are NOT going to serve.”

Some founders try to optimize for multiple personas to expand their market opportunity. However, this is a big mistake. This is also common among first-time founders who think this is what investors want to see. It is not. It’s much more powerful to have a narrower set of users who love your product vs. a broader set of users who kind of like it. Successful companies are built on products that have a diehard group of users who love a product so much that they will tell others about it. Don’t be afraid to narrow your focus and deliver an exceptional product. You can build on that success later.

Key takeaways: Personas are a handy way to get everyone in the organization aligned around who the target audience is. The more specific you are with your defined personas (name, background, photo, description of usage), the more helpful they will be. Focus on a few personas and over-deliver in terms of a great product for those users.

5. Launch and learn!

With each step of the process, you should be gaining confidence that you are on to something special based on the feedback from your target users (i.e. your die-hard fans). Ideally, you are measuring the level of enthusiasm for your product in the market. Still, there is no bright line that will tell you that you are ready to launch. Even after months of testing, many founders hesitate to launch. There is always a long list of things that haven't been built yet, but don’t let perfect be the enemy of the good. There comes a point where broader usage is necessary to continue learning. If fact, if you have followed these steps, launching might be the best way to continue to learn.

One signal that can help you know that you are ready to launch is when customers are clamoring for the product and want to tell others about it. If you have been successful in finding product-market fit, there should be demand from the market asking for the product and wanting broader usage. In fact, your users should need the product and be demanding that you launch it. And if you have gone a step further and quantified the level of interest, then you should see a strong base of users (40% or more, according to Sean Ellis' research) who can’t live without your product.

For Nextdoor, the clear sign to launch was when friends of friends started asking if they could bring Nextdoor to their neighborhood. Not only did these users depend on Nextdoor, but when they told others about it they wanted it too. That was a strong signal that we were a product people wanted and needed.

With that support, we picked a date and ran furiously to get everything ready for a big press launch and broader usage. But three weeks before launch, we kept hearing feedback about needing faster methods for new users to verify their address. We debated adding the functionality after launch, but ultimately decided to delay launch by three weeks to add a phone-based method for address verification. We felt like we needed the best registration flow possible to make the most of the one-time launch event. With more than twenty national press articles, we were glad we took the three weeks to implement the change and help us leverage our national launch to accelerate growth.

Key takeaways: When users are clamoring to share your product with others, it’s time to launch into the market. Even if there are shortcomings in your product, you need to pick a date and go for it. The launch will galvanize a team to work towards an explicit date. But don’t be foolish and rush the process if market feedback suggests you need to build something to make the most of the launch. Recognize that the launch event is just another step in your refinement of the product. If you’ve targeted a big market, you will have many product-market fit moments ahead of you. This process can and should be used continuously to gather feedback and hone the product.

I put together this Core Hypothesis and Personas Worksheet, which you can use to kickstart your own process.

The overarching mindset I encourage founders to embrace on this journey is to have “bold opinions, weakly held” at the start. Great entrepreneurs have an insight (or “opinion”) about how the world should work better and then must go out to the market to pressure test that opinion until they get it right. To do that, an entrepreneur needs to be confident enough to form a new opinion, but also humble enough to know they have blind spots that they must uncover and address in order to build something valuable.

There will always be the risk of failure when launching something new to the market. The beauty of this quest for product-market fit is that you can dramatically improve your chances of success with these pre-launch steps that help uncover the nuanced needs of the market. And that can make all the difference between success and failure.

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