Why Every Startup Needs A Killer Product Use Case
“A killer use case is the single occasion where your product is the best available answer to a burning problem for one specific group of people. Picking one feels like closing doors. Picking several is what actually stalls companies, sometimes for years. This piece covers what makes a use case killer, three ways founders avoid the decision, and how to find yours.”
Startups often assume a use case is just how you tell customers to use the product. It's the decision that gives a small company one point of pressure it can put its whole weight behind, which is how startups take territory from global incumbents.
Building a startup is all-consuming, and that fixation leads founders to assume everyone will see how obviously valuable the product is at a glance.
They won't.
Users can't work this out for themselves. As the builder, your job is to tell them why they should care and when they should use it. For almost every product, including yours, users don't initially care how it works. They want to know why and when.
The "when" is the product use case: the occasion or context where your product is the right answer to the problem your target users face.
What is a killer use case for a product?
Product use case turns into product use cases very quickly. Adding that "s" is a shortcut to insignificance for a new product. Instead of a landing page listing half a dozen ways users could implement the thing, the best startups find one.
Your product has a killer use case when it is the best available answer to a burning user problem. That implies a reason why your product beats every alternative for this specific problem. Four kinds of differential advantage produce that.
Feature advantage
A technical aspect of your design or functionality that makes the product faster or better for one problem users care a lot about. Typeform, the design-led conversational survey tool, offers better design and more customisation than the category incumbent SurveyMonkey.
Cost advantage
A well-executed pricing strategy can be a differential advantage, and that doesn't always mean cheaper. Competing on lowest price alone commoditises a category and usually starts a race to the bottom.
AVG's antivirus product is the version done well. It pioneered a freemium model in the mid-2000s and ended up on almost every home and office computer. Price became part of the distribution strategy, and users experienced the value before there was any reason to pay.
Support advantage
The name undersells it. This now covers community, personal assistance like customer success managers, and increased customisation or flexibility. Notion, the flexible knowledge management platform, accelerated its growth by putting community at the centre of its strategy.
Status advantage
Always a factor in product strategy, and increasingly a leading point of differentiation among software startups. Superhuman combined grey-labelling with a very long sign-up waiting list to build cult status around an email client.
Where does a killer use case fit into product strategy?
It's one of the core components of your proposition, sitting at the intersection of three things: your differential advantage, a well-defined persona, and a high-priority problem.
Miss any one and you don't have one. An advantage with no problem attached is talking about yourself. A problem with no advantage behind it helps a competitor close. And without a defined persona you're guessing at both, which is why needs-based segmentation usually comes before this decision, not after it.
Why is a killer use case important?
For the user, it says exactly what problem your product solves, which gives them the context for your value proposition. Unless you tell people where the product fits into their life, they won't work out how it adds value to it.
For the company, it defines the territory you plan to take from incumbents. That tactic is commonly called unbundling: taking one use case from a tool that offers many, then serving it better and often growing the total market in the process.
This is David against Goliath. You only beat Goliath by putting everything behind one point of pressure.
Examples of killer product use cases
One look at Intercom's website from February 2017 told you what they did.
^ Intercom's landing page in February 2017
By that point Intercom had closed a $50 million Series C and had well over 100,000 monthly active users, a meaningful share of them paying. Even with that traction, the killer use case stayed obvious: Intercom makes customer interaction personal and simple.
Here are the three most common ways founders avoid choosing one.
Pitfall 1: Picking more than one use case
First-time founders look at big tech companies promoting multiple use cases across multiple customer segments and assume they can do the same.
^ zoom.us landing page, June 2021.
Look at Zoom. But remember you're looking at Zoom the scaleup, not Zoom the startup. They can run eight propositions across four personas because their market already knows who they are. Say "Zoom" to anyone and they think of video calls before they think of a camera lens or a cartoon character.
Category leadership buys the breathing space to expand across segments and use cases. A startup has none of it, which is why picking one territory is the only move available to David.
Zoom wasn't always Goliath. In June 2014, Zoom the startup was a new product making video conferencing considerably better for companies doing business online.
^ 'Zoom the Startup' (June 2014 via the Wayback Machine) has a clear focus on business video conferencing
Every one of these giant companies started with one killer use case. The other seven propositions came much later.
Pitfall 2: Expecting users to figure it out themselves
One version of this is a product that offers no use case direction at all. The more common version is subtler and does more damage.
Early traction usually comes from experiments that eventually find the right combination of persona, problem, proposition and product. Our own idea validation went the same way. It's rare that every customer from that experimentation comes from one segment.
Founders are close enough to the work that early signs of product/market fit read as a green light, so they call in venture capital and add fuel to the rocket. The trouble is that a rocket serving multiple segments doesn't ascend the way anyone planned.
What happened at HubSpot
HubSpot found organic pull within a year of starting. It took six more years to work out how to scale customer acquisition without wrecking the ratio between lifetime value and acquisition cost.
In Brian Halligan's own account of the period, hiring faster made the maths worse and slowing down made it better, which left the company with an interesting business and no way to accelerate it. HubSpot sat in that limbo for years.
Hubspot's landing page in June 2011 (via Wayback Machine). The tell on that 2011 page is the phrase "all-in-one", which translates to doing several things reasonably well for several different types of people. Even the customer successes section shows two audiences: marketing managers and business owners.
Halligan calls the fix the Mary-MOFU-Monetization playbook, which is three decisions in a trench coat. The MOFU part is the one about use cases.
Until then, HubSpot had five product teams building for two use cases: top-of-funnel marketing, meaning tools that drive visitors to your website, and middle-of-funnel marketing, meaning tools that turn those visitors into leads. When Halligan set out to decide which to cut, the data gave him a surprising answer.
The top-of-funnel tools were the better product. The middle-of-funnel tools were, by his own description, crappy. Customers using the crappy ones retained better.
^ Hubspot in June 2013 (via Wayback Machine). Their proposition is much clearer after doubling down on one use case and one persona.
Look at HubSpot today and you'd never realise how essential that decision was to their early success. Use case strategy is a completely different problem for an early-stage startup than for a growth-stage scaleup.
^ Hubspot CRM landing page in June 2021 (via Hubspot.com). That page is one of five HubSpot products and it alone targets six personas. HubSpot built an entire organisation capable of that level of segmentation. Notice their positioning has drifted back toward having something for everyone, which is exactly how space opens up for a new startup to claim territory with a more specialised product.
“Sitting on the fence with more than one use case does not keep your options open. It creates an optionality tax that can stifle growth for years.”
Pitfall 3: Templates are not use cases
Most early-stage products add templates as a crutch to avoid putting their full weight behind one use case. This applies particularly to products that haven't hit their pull point yet, and to products not built around creativity or customisation like website builders and design tools.
We made this mistake at OpinionX. Users kept requesting templates because they weren't sure how to use the product. Those requests were telling us people didn't know what to use OpinionX for. They were not asking for a one-click template gallery.
Feature requests are a route to understanding the barriers in your product, not a pipeline of ideas to fill your roadmap with. Prioritisation techniques come after that diagnosis, not instead of it.
How your use case determines your acquisition strategy
This decision informs your entire customer acquisition strategy, and here's how that played out for us.
In early 2021 we faced a hard choice at OpinionX. We were seeing organic traction and signs of fit across persona, problem, proposition and product. As product/market fit tends to be, it was blurry. We couldn't tell whether ours should be "validate your new product idea" or "find product/market fit faster".
Those sound like the same problem. There's one enormous difference: validation happens before you build, and finding product/market fit is an ongoing process that runs while you build.
Our primary acquisition channel is SEO through content. Both use cases have plenty of good keywords. But SEO needs a signal to intercept, meaning someone searching for an answer to a question.
A founder decides on their validation method before they start building, so the signal is far smaller, and often it never happens at all. Product/market fit generates countless signals along the way, because builders hit obstacles constantly and go looking for answers. It also never really ends, since every new segment or use case restarts it.
So picking "validate your new product idea" would have meant finding other channels to reach people before they started their next idea: partnerships, workshops, getting in front of them early. Picking "find product/market fit faster" gave us a stack of bottom-of-funnel searches where we could be useful, which I assume is working if you found this article.
How do you find your product's killer use case?
The best killer use case is the intersection of three ingredients: a burning problem, experienced by a well-defined niche segment of target customers, where your differential advantage makes your product the best answer.
Three common approaches for identifying one.
Product metrics
Reactive research is common for segmentation at larger companies with established processes for tracking quantitative behavioural data through tools like Mixpanel or Google Analytics. This is how HubSpot discovered their middle-of-funnel products retained better. If you have plenty of behavioural data, Mixpanel's guide to behavioural segmentation is a good starting point.
User interviews
Most teams don't have that much data, and even the ones that do can't learn why users behave a certain way from quantitative data alone. So almost every team ends up running interviews to understand each segment's needs.
Your objective is to identify the most important problem interviewees are trying to solve within the occasion you're focused on. Best practice is to ask non-leading questions that get people talking about their lives, then wait to see whether the problem comes up on its own. If it does, across enough interviews, it's a genuine priority.
Interviews look easy. In practice they're simple to misinterpret and easy to ruin with a leading question, and there are three mistakes founders make at exactly this point. If you take this route, read The Mom Test by Rob Fitzpatrick first. It's short and it will save you from the common mistakes.
Customer problem stack ranking
During those interviews, you're trying to see whether the problem you plan to solve is among your target customers' most burning. Solve a burning problem and getting people to pay you stops being hard. Problem libraries like 99 startup problems and B2B customer problems are a place to start if the list is blank.
Instead of hunting for patterns across tens of hours of interview transcripts, Customer Problem Stack Ranking does the same job in an afternoon. Named by Shreyas Doshi, then a product leader at Stripe, it asks target customers to stack rank a list of problem statements so you can see which ones are the highest priority for the largest group of people.
^ When you use Customer Problem Stack Ranking, this is how easy it is to identify the right burning pain point to build your Killer Use Case around.
We spent months and 150+ user interviews validating our startup idea and building our original value proposition. In under two hours, a stack ranking survey showed us that the problem we claimed to solve was among the least important problems our target customers had. We rewrote the website around the highest-ranked problems instead, and our traction multiplied.
Conclusion
No product builder gets out of the killer use case decision. You can defer it, and I did, for about a year.
^ David, co-founder of Mo.na, a platform for creators to sell their skills, put me back in my place when I was trying to dodge the decision. His point was counterintuitive and correct: the smaller the initial opportunity seems, the better.
I spent a fair share of the first year building OpinionX fighting to avoid picking one use case. I even DMed founder friends looking for reassurance that it was a decision I could defer. I was wrong.
Don't do what I did. Go looking for yours deliberately, starting with your target customers' biggest problems, which is the fastest route to it.
Frequently asked questions
What is a killer use case?
The single occasion or context where your product is the best available answer to a burning problem for a well-defined group of customers. It sits at the intersection of a differential advantage, a specific persona and a high-priority problem, and missing any one of those three means you don't have one.
Why should a startup pick only one use case?
Because serving several means serving none of them convincingly, and the cost is invisible until it stalls you. HubSpot found organic pull within a year and spent six more years unable to scale acquisition, because they hadn't chosen between two use cases and two personas. Halligan calls that cost an optionality tax.
What are the four types of differential advantage?
Feature advantage, where a technical aspect makes the product better for one specific problem. Cost advantage, where pricing strategy becomes a distribution mechanism. Support advantage, covering community, customer success and flexibility. Status advantage, where the product confers something on the person using it.
How do you find a killer use case?
Three approaches. Behavioural product metrics, if you have enough usage data. User interviews, which almost every team needs regardless. And customer problem stack ranking, which asks target customers to rank a list of problems directly and returns an answer in an afternoon instead of weeks.
Are product templates a use case?
No, and reaching for them is usually a signal that you have avoided the decision. Template requests generally mean users don't know what to use your product for, which is a positioning problem rather than a feature gap.
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