Theranos, Fyre Festival, Nikola Motors etc. did one thing all these "tech" scams do.
Defy the Laws of Physics - the time required. The speed limit of tech is what investors, SPAC's etc. are all pushing up against nowadays. There's billions $ out there but the crop takes time to grow.
If you don't have any money, sell a fantasy, some product yet to be made. Pre-sell, get orders before you have anything tangible
(a festival is not tech but professionals knew these events take years of planning (and an island with space, sewer, water, facilities, no sharks) yet the whole thing ripped along faster than feasible).
With technology, that's an expected ("the schedule") failure because large portions of it are non-deterministic. How long to invent that tech? When will it be ready? You can't know or forecast it.
Compare with manufacturing. Making a Big Mac, scheduling that is easy. All the parts are known, in stock and just a delay to cook the pattie and assemble the burger.
I once told an old boss, "you could put 100 engineers on the project and it wouldn't go any faster". Himself, exec's business MBA types just don't understand why they can't clap their hands and tech projects miraculously speed up as they "push the engineers".