The Simple Startup Framework: Why “Time to First Invoice” Is All That Matters
Every startup dreams of disruption. Of Series A rounds. Of traction graphs and keynote stages. But here’s a reality check:
Most startups fail not because of poor technology, but because they don’t know how to buy or sell.
Sounds harsh? Maybe. But I’ve seen it happen too often — teams that can build a product, but not a business.
So let’s reframe the startup journey around one very simple idea.
🧭 The KPI That Changes Everything: Time to First Invoice
Forget vanity metrics for a second.
The most critical KPI in any startup is this:
🕒 Time to First Invoice (TTFI)
How long does it take until you send your first invoice to a customer?
It sounds trivial — even funny — but it's profound. Why?
Because a paid invoice proves that:
✅ You have a product (or service, license, prototype…)
✅ A customer exists, and they’re willing to spend
✅ You can produce and deliver the value
✅ You know your price
✅ You’ve managed to formalize the exchange
In short: you’re in business.
Until that point, you’re just building.
💡 The Problem: Startups Don’t Know How to Buy or Sell
Even with great tools like the Business Model Canvas, Lean Startup, or Design Thinking, many startups still fail at the basics.
Here’s what I’ve seen:
Building Block Startup Reality Selling No pricing strategy, vague value proposition, fear of rejection Purchasing No supplier scouting, unclear specs, unrealistic delivery assumptions Delivery No process, no timeline, no quality expectations Product Blurred boundaries, endless scope creep Focus Too many hypotheticals, not enough transactions
Frameworks are great — but they often stop at the theory.
“Time to First Invoice” forces teams to test reality.
🔧 A Simple Framework to Align Action
Let’s break this into three core phases — all aligned to the moment of getting paid.
1. Can You Define What You Sell?
Name it. Describe what it is — and what it is not
Is it a product, a service, a subscription, a license?
What is the smallest unit of value someone would pay for?
💡 Use with:
Value Proposition Canvas · User Stories · MVP logic
2. Can You Deliver It — Once?
What’s your Bill of Materials (even for services)?
Who do you need — suppliers, freelancers, systems?
What does delivery look like: digital? physical? in-person?
💡 Use with:
Service Blueprints · Lean MVP principles · Supply Chain Mapping
3. Can You Get Paid For It?
Do you know how to price?
Can you send a quote? A contract? An invoice?
Do you know the tax/legal basics?
💡 Use with:
Basic Sales Funnel · CRM (even a spreadsheet) · Cash Flow Simulations
🔁 Reverse Engineer from Payment
Sometimes the best way to define your business is not to start with your idea — but with your first transaction.
What needs to be true for someone to actually pay you?
By working backward from a paid invoice, you uncover:
What was sold
To whom
For what value
How it was delivered
Why they trusted you
This cuts through pitch-deck fiction and forces practical answers.
📌 Side Note: A Practical Mindset from the Field
“Reverse Engineer from Payment” isn’t from a textbook.
It’s a hands-on approach I’ve developed through mentoring startups who struggled to define what they were actually selling — until we worked backward from the only thing that truly validated their offer: a paid invoice.
Think of it as a shortcut to clarity. It forces you to cut through the noise and answer:
Who paid you, for what, and why?
🧑🏫 Workshop Exercise: Build to Invoice
In your next startup workshop, ditch the pitch deck. Try this instead:
Design your first invoice.
What is it for?
Who is it sent to?
What is the price?
What did you need to do to get there?
If your team can’t answer these questions, go back to the drawing board.
If they can — you’re on your way.
💬 Final Thought
Forget scaling before selling.
Forget product-market fit before revenue.
The first sign of life in any startup is the moment someone pays.
So ask yourself:
How fast can you get to your first invoice?