There should be better ways to know how to "value an idea.". I believe that there are better ways, that the VC-startup world does poorly there with biggie costs on the both sides of the table, that there are some good examples of the ways, and that, really, we are awash in both how to do this and examples.
First, we start with evaluating ideas. Gee, guys, the research community does that many times daily. A researcher who pursues dumb ideas in a few years is known as a poor researcher. So, good researchers know how to evaluate ideas.
The researcher's superiors, the proposal reviewers, and the funding agencies also all know how to evaluate ideas and where here the ideas are just research directions with the ideas not really formed yet.
Moreover, for publication in peer reviewed journals of original research, the standard criteria for evaluating the ideas in a paper are "new, correct, and significant", and these criteria get applied with good accuracy.
Moreover, for a Ph.D., one way to evaluate the work is "an original contribution to knowledge worth of publication." And, before a Ph.D. student starts their research, they and usually also their faculty advisers have to evaluate the research direction, even before a solid idea.
The US NSF, NIH, DARPA, ONR, etc. are also quite good at evaluating research directions well before a finished idea.
Of course we can evaluate ideas, especially ideas already polished and ready for publication and also finished, polished ideas already implemented in solid, running code.
Then, sure, that evaluation does not necessarily lead to business success, that is, traction, revenue, earnings, money in the bank, an a good ROI and exit for investors. Right.
But, wait, there's more!
Second, here's a severe way to evaluate such a polished idea ready or nearly so to go for first traction: Or, with the running software, can see that it works. Now the severe question is, "Is that software a must have solution with enough users/customers and revenue per each to make the big bucks or is that software just a nice to have and/or for just a niche?" And we will want to know about barriers to entry, scalability, etc. Doing well on these criteria should be darned good signs.
Apparently instead the VC community wants to judge based almost entirely on traction and rate of growth in traction. Yes, that's hard headed; it's also dumb headed, ignoring important information.
Some businesses do quite well with new ideas:
Xerox did well with the research direction of electro-static photocopying -- from just the research direction through creating a major company.
At each smaller step in line width, Intel does well. Who would have believed 1 billion transistors on a postage stamp with line width 14 nm?
The pharmaceutical companies that do original research make their money on picking good research directions and then doing good research.
And may I have the envelope, please [drum roll]!
The all-time, unchallenged, unique
world-class, grand champion of going from mere research directions to world changing results is the US DoD. Second and third places are occupied by the NSF and NIH. Intel, some of the pharmaceutical companies, and more are also on the award stage. VCs need to start learning up from those examples.
The VC approach would have been, "You build and test the first one, and we will chip in for the gasoline for the Enola Gay."
Instead, IIRC from books of Richard Rhodes, the Manhattan Project cost ballpark $3 billion in 1940's dollars.
Okay, big, expensive waste just from war time, right? Maybe not: Let's divide $3 billion by one million -- right, even without a super-computer, that's $1000.
And the relevance? The estimates were that a US invasion of the home islands of Japan would cost the US 1 million casualties. Given the experience at Okinawa, Iwo Jima, etc., the 1 million was believable. So, the Manhattan Project saved expected 1 million casualties at, right, from the arithmetic, $3000 per casualty. Grand bargain just from the money alone! If your father, son, brother, uncle, etc. were one of those casualties, then you would have regarded the $3000 as a grand bargain.
And the Manhattan project spent money like it was worthless -- cost no object or concern. Good ideas are like that.