Pedigree of the team and a believable project plan.

Often times money will be raised at certain valuation and terms, but the cash is held in escrow (effectively) until milestones are hit.

The investors will do their due diligence on the feasibility. It’s a high stakes, high return game (if you succeed). Look around you… any physical device you see is basically funded the same way.

That’s like the point of venture capitalism and to a certain extent all entrepreneurial endeavors. You could start a T-shirt printing company (a completely viable business) and not see any revenue come in for months.