Seek a strong response from a narrow group

Choose a first customer group with a clear shared need. Learn why those people use the product and when they stop. A narrow group makes patterns easier to see. A claim that everyone is the customer usually makes the evidence weaker.

Early enthusiasm is useful, but behavior matters more. Look for repeat use, payment, referrals, and effort made to obtain the product. These signals differ across businesses. No single number proves that every product has found its market.

Strong demand can change the operating experience. Customers pull the company forward, and delivery becomes harder to keep up with. That does not remove the need for judgment. You still need to understand whether the demand can support a durable business.