- Build, by Sefunmi Osinaike
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- The Math Has to Work
The Math Has to Work
Issue#9: Understanding Unit Economics Before They Humble You
In 2013, four Stanford students had a problem: they were hungry, busy, and didn’t want to drive across Palo Alto for food.
They found out that other students faced the same problem.
So they built a scrappy site called Palo Alto Delivery.
It listed a few local restaurants, let students order online, and the founders delivered everything themselves.
The concept was simple: help people order food, fast.
That project became DoorDash.

When they started, DoorDash was the underdog.
Uber Eats had more money, Postmates had the brand, and Grubhub had the head start.
But ten years later, DoorDash owned over 50% of the U.S. food delivery market, surpassing them all.
It was not because they had the best app or the loudest brand.
They won because they understood something better than anyone else: The numbers had to work.
While competitors chased urban foodies in high-rise apartments, DoorDash looked out to the suburbs with big homes, big families, and big dinner orders.
So instead of delivering one burrito to a guy on the 12th floor, they delivered $50 meals to households in the outer edges of Atlanta, Dallas, and Phoenix.
The cost of delivery didn’t change, but the revenue per trip was much higher.

In startup terms, that meant stronger unit economics.
If it cost $6 to fulfill an order, and they only made $8 from it (or less), there wasn’t much room to grow.
But if they could push revenue to $25 or $30 without raising costs, they’d have real leverage.
And that’s exactly what they did.
The result?
Better margins. Shorter payback periods. More room to scale without breaking the bank.
Why Unit Economics Matter
A lot of startups die not because they didn’t get users, but because they didn’t understand the cost of serving them.
That’s where unit economics come in.
At its core, unit economics is just one question: Can you afford to serve one more customer?
Here are three numbers that make or break your unit economics.
1. CAC – Customer Acquisition Cost
This is how much it costs to get one person to try your product.
That includes everything: ad spend, influencer deals, referral bonuses, sales commissions, even the time your team spends chasing leads.
If you don’t know your CAC, you don’t know what growth is costing you.
2. LTV – Lifetime Value
This is how much revenue a customer brings in over their entire time with you.
It’s a reflection of how often they come back, how long they stick around, and how much they’re willing to pay.
A high LTV usually signals product-market fit. A low one? That’s often a churn problem dressed as a growth problem.
3. Payback Period
This is how long it takes for a customer to “pay you back” for the cost of acquiring them.
If you’re spending $100 to bring someone in, but it takes 12 months to make that $100 back, you’re playing a losing game.
The shorter the payback period, the more flexibility you have to reinvest and grow.
What DoorDash Got Right
Let’s break it down.
They launched where others wouldn’t.

While competitors targeted flashy urban markets, DoorDash looked to the suburbs - places with families, higher order values, and fewer delivery options.
That decision was driven by margin, not ego.
They maximized value per trip.
Delivering a $50 family meal costs almost the same as delivering one $12 salad.
But one actually makes money. Guess which one they chose?
They started manually.
In the early days, founders Tony Xu, Andy Fang, and Stanley Tang delivered food themselves.
It wasn’t scalable, but it gave them visibility into what broke and what worked.
That clarity shaped everything that followed.
They treated restaurants like partners.
DoorDash offered restaurants more than logistics.
They built dashboards, surfaced data, and helped restaurants optimize menus and pricing.
That meant stickier relationships and lower churn on the supply side.

A DoorDash Dashboard
They didn’t overcorrect for growth.
Even as funding poured in, they stayed disciplined.
Every new market was a calculated bet, not a land grab.
The takeaway?
They didn’t need to win the whole country overnight.
They just needed to win the right parts, profitably, and let compounding do the rest.
Builder’s Playbook: How Canva Made the Numbers Work Before Scaling

Melanie Perkins - Co-Founder and CEO of Canva
When Melanie Perkins co-founded Canva in 2013, they didn’t try to replace Photoshop overnight.
They focused on non-designers who needed to create simple graphics without help.
Think marketers, teachers, and small business owners.
This group had clear needs and high repeat usage. They created presentations, posters, and social media content week after week. Canva made that process easier and faster.

That made the business model work.
Here’s how Canva kept unit economics in check from the beginning:
Free-to-paid conversion was strong. Canva’s free tier gave users real value. Those who needed premium features like templates or brand kits were happy to pay. This created a healthy LTV without relying on discounts or aggressive upsells.
Customer acquisition cost stayed low. Most users found Canva through organic channels like word-of-mouth, YouTube tutorials, and templates shared online. That meant minimal spend to bring in high-intent users.
High retention across use cases. People who created their first design often came back for more. Teachers made classroom posters. Marketers made LinkedIn graphics. Businesses created pitch decks. That repeat behavior kept churn low and lifetime value high.
Clear path to profitability. Canva didn’t burn cash chasing every user. They prioritized segments that activated quickly and generated revenue. That gave them breathing room to reinvest without constantly raising money.
Gut Check: Run the Numbers

This week, block out 30 minutes and ask:
What’s your CAC (really)?
What’s your actual payback period per user type?
Which customers stick around and spend more?
Which ones drain support, churn early, and never refer anyone?
You don’t need perfect answers, but you do need visibility. Because what you can’t measure, you can’t improve.
🤖 Helpful AI: Sturppy
Each week, we spotlight a digital tool, AI resource, or business hack that can help you streamline processes and boost productivity.
This Week’s Pick: Sturppy 🌐🚀

If you're running a startup but don’t have time to build complex financial models, Sturppy can help.
It’s a financial planning tool designed for early-stage founders — no spreadsheets or finance background required.
Use Sturppy to:
Forecast revenue and track burn with real-time visibility
Calculate CAC, LTV, and payback period with simple inputs
Model different growth scenarios to guide better decisions
It’s a faster way to understand your numbers and plan for scale — without hiring a finance team.
Resources to Bookmark
📘 The Cold Start Problem – Andrew Chen
How retention and network effects shape LTV.
Get the book here
🎧 Acquired Podcast: DoorDash
A 2+ hour breakdown of their strategy, from hustle to IPO.
→ Listen here
📄 Baremetrics Benchmarks
Compare your CAC, churn, and MRR growth to thousands of SaaS companies.
See it here
Audience Corner
What’s one number in your business you’ve been avoiding but probably need to face?
(LTV? Churn? Payback period?)
Reply and tell me what it is - and what’s been holding you back from digging in.
Final Thought
Unit economics aren’t just for your pitch deck.
They’re the difference between building a brand and building a business.
Before you scale, before you hire, before you raise again, make sure the math works.
Because once it does, growth isn’t scary. It’s inevitable.
Till next time,
Sefunmi.