Knowing where your first users are is a prerequisite to starting a startup
I talk to 15-20 founders each week about their growth needs, and occasionally, I have to deliver this feedback...
"𝘐𝘧 𝘺𝘰𝘶 𝘢𝘳𝘦 𝘣𝘶𝘪𝘭𝘥𝘪𝘯𝘨 𝘢 𝘱𝘳𝘰𝘥𝘶𝘤𝘵 𝘢𝘯𝘥 𝘵𝘳𝘺𝘪𝘯𝘨 𝘵𝘰 𝘢𝘤𝘲𝘶𝘪𝘳𝘦 𝘺𝘰𝘶𝘳 𝙛𝙞𝙧𝙨𝙩 𝙪𝙨𝙚𝙧𝙨 𝘣𝘶𝘵 𝘥𝘰 𝘯𝘰𝘵 𝘬𝘯𝘰𝘸 𝘸𝘩𝘦𝘳𝘦 𝘵𝘰 𝘧𝘪𝘯𝘥 𝘶𝘴𝘦𝘳𝘴, 𝘺𝘰𝘶 𝘮𝘪𝘨𝘩𝘵 𝘯𝘰𝘵 𝘣𝘦 𝘵𝘩𝘦 𝘣𝘦𝘴𝘵 𝘱𝘦𝘳𝘴𝘰𝘯 𝘵𝘰 𝘣𝘶𝘪𝘭𝘥 𝘵𝘩𝘪𝘴 𝘱𝘳𝘰𝘥𝘶𝘤𝘵."
Here's why...
People are best at solving problems they experience, meaning that their first users are like them. Their first users hang out where the founder hangs out online and IRL. Their first users have tried the solutions that the founder has tried, so they have the same dissatisfaction with the current solutions. The founder is the first user, so a better product attracting the right first users is more likely to be built and shared in a space where the first users hang out.
Great founders are relentlessly resourceful and have a bias for action. Even if the founder has simply observed a problem from a distance, they dive in and immerse themselves in the problem. Great founders have the grit and the drive to quickly learn about the problem and the space it occupies.