Here are some non-quantifiable things that matter:
1. Grit/High Pain Tolerance. People who do not give up, often to the detriment of their physical, mental, and/or emotional health.
2. Structure. People who can organize — whether in their head or on paper — their business. Who is the customer, what is their problem, how do we solve it, how do we find them, why is our thing better than their thing, etc.
3. Prioritization. People who can look at the things to be done and know which are more important.
4. Communication. You have to be able to talk to people. Not talk at people, but with them as an exchange of ideas. Growing your business (sales), your team (hiring), your brand (PR), and fundraising are all reliant on your communication skills
5. Intelligence. The bar here is lower than is assumed. You don't have to be galaxy brained, but basic smarts.
6. Willingness to seek, sort, and take action on advice. You have to ask for help, but not all offers of help are useful or relevant or correct. And then you have to actually do the thing.
7. Giving up control over things you're not good at. It's good to fire yourself when you're bad at something.
You can find a whole mix of these. I know founders with high grit who work on the wrong things. I know founders who prioritize incredibly well but don't have a full structure of the business in their heads and so get blindsided by an unknown unknown.
I know founders who are monetarily tremendously successful that lucked into a market (some of whom were dragged into that market by others), but, were things to take a turn, their boards would fire immediately.
There is certainly a scale. You don't have to be 10/10 on all of them to be "great".
But the thing is — and I think this is something people have a hard time wrapping their heads around — is that when you sum all of this up, you're only increasing your odds. The odds are still minuscule that you will get lucky enough (many times over) to be in a position to have a massive company. There are excellent founders who fail for things entirely outside of their control.
Walter Isaacson recognized this when he went to write his book The Innovators [0]. He intended it to be a more narrow autobiographical book like he is known for but quickly realized the technological revolution was brought about through an collaborative effort across time and space.
[0] https://www.goodreads.com/book/show/21856367-the-innovators
I HIGHLY recommend tech workers to actually break out of your bubble. So much of our ethos is being "free thinkers", but most of the "thought" is just repeated business pep talk.
I've heard this repeated dozens of times, and I believe it is just circular logic.
1. The success of the startup depends on the quality of the founder.
2. The quality of the founder is determined by whether or not their startup succeeds.
I think some people would argue that they aren't judging the quality of the founder by whether or not their startup succeeds. But I don't know if I buy that. If some "low quality founder" creates a billion dollar business people will just say "I mis-judged him. He's a great founder." If some "high quality founder" creates a startup that fails people will say "He just didn't have what it takes as a founder", until he eventually succeeds then they'll be back to "He was a great founder all along".
In other words, every founder of a successful startup is a "great founder". But only because that is baked in to the definition, despite the implication that you're actually judging their merit as a founder in some other (mysterious) way.