Made-Up Ideas and the Sitcom Trap
When you set out to think of a startup idea, you usually get what PG calls a sitcom startup idea: something a writer would invent for a TV character to be founding. It sounds like an idea. It has the shape of an idea. Nobody actually needs it.
The trap is that made-up ideas don't get cleanly rejected. Show one to friends and they won't say 'I would never use this.' They'll say 'Yeah, maybe I could see using something like that.' Sum that lukewarm reaction across the entire population and you have zero users.
PG paid this tax personally: months spent building an online gallery for art dealers who, it turned out, didn't actually want to be online. The idea sounded reasonable. Nobody had the problem.
Key idea
Made-up ideas fail slowly because people say 'maybe' instead of 'no'. Lukewarm interest multiplied across the whole world is still zero users.