Run a YC-style product diagnostic before building

The Problem

Engineering time is the most expensive resource in a startup. A single engineer working for three months on the wrong feature costs $50,000-$100,000 in salary alone, plus the opportunity cost of everything they could have built instead. Yet teams routinely commit engineering resources to ideas that have not survived basic scrutiny.

The problem is not that founders and PMs lack judgment. It is that they lack a structured forcing function to pressure-test their assumptions before building. Y Combinator has funded over 4,000 companies, and their partners consistently report the same observation: the teams that fail fastest are the ones that skip the diagnostic questions and jump straight to building.

CB Insights analyzed 110 startup post-mortems and found that 42% of startups fail because there is no market need for their product. Not because the product was poorly built. Not because the team was weak. Because no one asked, rigorously and honestly, whether the problem was real and the solution was wanted.

According to the Startup Genome Project, startups that validate their idea before scaling are 2.5x more likely to succeed than those that scale prematurely. Validation is not optional. It is the highest-ROI activity a product team can do.

Six Questions, Not Six Months

You do not need a six-month research project to validate an idea. You need six questions asked honestly and answered with evidence, not hope. The YC diagnostic is designed to kill bad ideas in hours, not months. The ideas that survive are the ones worth building.

How This Prompt Works

This prompt runs a YC-style product diagnostic that subjects your idea to the same forcing questions that YC partners use to evaluate companies. It is designed to be uncomfortable. Comfort is the enemy of clarity.

The diagnostic covers six questions:

• Who is desperate for this? Not "who would use this" but "who would be devastated if it did not exist?" If you cannot name specific people with specific pain, the demand signal is too weak.
• What do they do today? Every problem already has a solution, even if it is a terrible one. If you cannot describe the current workaround in detail, you do not understand the problem deeply enough.
• Why now? What has changed in the market, technology, or regulation that makes this solvable now when it was not solvable before? Without a "why now," you are competing on execution alone.
• What is the narrowest possible wedge? What is the smallest version of this that delivers meaningful value? The narrower the wedge, the faster you can validate demand.
• What did you observe that others missed? What unique insight do you have from direct observation, not from reading TechCrunch? The best ideas come from noticing what everyone else overlooks.
• Where does this go in ten years? Is this a feature, a product, or a company? The answer determines whether it is worth the investment.

The prompt guides you through each question with follow-up pressure testing. The output is a diagnostic scorecard with a clear build/kill/pivot recommendation.

When to Use It

• Before committing engineering resources to a new product or feature
• When evaluating whether to pursue a new market or customer segment
• During ideation, to quickly filter a list of potential bets
• When you suspect the team is in love with a solution instead of a problem

Common Pitfalls

• Being too generous with your answers: The diagnostic only works if you are brutally honest. "Lots of people probably want this" is not an answer. Name the people.
• Skipping the "Why now?" question: This is the most frequently skipped question and the most important one. Without a structural tailwind, you are relying entirely on execution, and execution alone rarely wins.
• Using it as validation theater: Running the diagnostic and then ignoring the results is worse than not running it. If the diagnostic says kill, have the courage to kill.

Further Reading

• The Top 12 Reasons Startups Fail - CB Insights
• Premature Scaling and Startup Success - Startup Genome
• How to Get Startup Ideas - Paul Graham