If you truly have a powder-keg idea, you should be doing everything you can to launch without formal investment because the second you spark that powder-keg your valuation will skyrocket. Traction trumps everything.
In other words, the more exciting the idea you're working on, the less plausible it is to say that you're waiting for investment to work on it.
Does this mean that only unexciting ideas require investment to get going? That's partially true (you can't start a corner shop without upfront investment), but it would be misunderstanding Gabriel's point.
The key take-away here is that "I have this awesome idea, I just need $100k to get started" is a bad pitch and isn't going to convince any smart investor.
