Validation
Stress-test your idea before you spend a dollar building it
Building is the expensive way to test an idea. Before you write code or spend on ads, run the idea through the questions that reveal whether there's a business underneath it.
Building is the most expensive test
Every idea feels validated in the founder's head. The cheapest place to find the holes is before you build, not after. A stress test is a deliberate attempt to break the idea on paper, where breaking it costs an afternoon instead of six months.
The five questions
Is it defensible — if it works, what stops the next person from copying it? Is the market big enough to be a business, not just a project? Will people pay, and how do you know beyond them saying they like it? Can you specifically build and sell this, given your skills, network, and runway? And who already does this, well enough that a customer has no reason to switch?
None of these are fatal on their own. Together they tell you whether you're looking at a business or a hobby with a landing page.
Answer honestly or it's theater
The stress test only works if you seek disconfirmation, not reassurance. If every answer comes back rosy, you're grading your own homework. Bring the hard version of each question, and treat a clear no as a gift — it just saved you the months you'd have spent finding out the expensive way.
- Building is the most expensive way to test an idea; stress-test on paper first.
- Five checks: defensibility, market size, willingness to pay, founder fit, competition.
- Seek disconfirmation — if every answer is rosy, you're grading your own homework.
Stress-test your idea in Cadenly
The Startup Advisor runs your idea through the viability questions founders skip — before you spend a dollar building.
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