I was talking to an entrepreneur yesterday, who was telling me he was waiting for funding to get started on his idea. The idea had a few flaws (the name was awkward, and the monetisation wasn't clear), but the main issue it had was that he hadn't started building it, because he wasn't technical.
I advised him to build a paper prototype of his product, go out and figure out the customer demand (perhaps get letters of intent or even purchase orders). Then, if the noises were positive, rope in someone to help him put a slightly more functional prototype, and keep getting more interest. Then, along with that, try to raise funding - I suspect that from doing this, he will get the feedback he needs to evolve his idea towards something workable - and may even raise funding once the idea is good enough.
But if he waits for funding before getting started, he'll never get started.
Ben Nesvig makes a related point:
The fate of your work lies in your hands. You don't need permission. You don't need the approval of a gatekeeper. No one will ever "discover" you in draft form.
In the startup world even more than anywhere else, you don't ask for permission: you do it, and then, if you totally screwed something up, you ask for forgiveness later.
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