Validating Your Idea

Why Validation Is the Most Important Step

Validation costs $0–$500 and takes 1–4 weeks. Building an MVP costs $10,000–$50,000 and takes 2–6 months. Startups that validate before building are 2–3x more likely to succeed. The return on investment is enormous — spending a few hundred dollars and a few weeks to avoid months of wasted building is a no-brainer.

The key insight from YC is that validation isn't a one-time event — it's an ongoing process. David Lee emphasizes cohort retention as the ultimate validation metric: "The only thing that matters is whether your cohort curves get flat."

Method 1: Customer Discovery Interviews

The most important validation method. The Mom Test framework: never ask if your idea is good. Instead, ask about their life, their problems, and their current solutions. People are naturally polite and will tell you your idea is great even when they have no intention of using it.

The most important signal is unprompted pain. When someone describes a problem without you leading them to it, that's a strong signal. Target: 20 interviews in 2 weeks.

Method 2: Landing Page Tests

The fastest way to validate demand at scale. Create a page describing your solution and measure how many people take action. Above 5% conversion is strong. Below 2% suggests your positioning needs work.

Method 3: Pre-Sales

The strongest validation signal. When someone gives you money for something that doesn't exist yet, you've learned something no amount of market research could tell you. Set clear success criteria before starting: "If 20 people pre-order at $49 in 2 weeks, I'll build this."

Method 4: Fake Door Tests

Add a button or link offering a feature that doesn't exist. When users click, tell them it's coming soon and ask them to join a waitlist. 5%+ click-through is a strong signal. Particularly useful for testing new features on existing products.

The 4-Week Validation Sprint

When to Build, Pivot, or Kill