This is a fair question in SaaS.
For me, the line is 10 Unaffiliated Customers. More on that here: https://www.saastr.com/if-you-ha…
To me, if you somehow have gotten 10 paying customers to find you — not your friends, your batch mates, your ex-boss — but 10 customers from the ether, then I know you have something.
That you can get 10 more. And then 100. And so on.
Less than 10? Sometimes, that falls back to 0. It may sound too precise, but SaaS startups with 2 or 3 paying customers sometimes end up with 0 in 12 months. But if you’ve gotten all the way to 10, you never go back to 0. Not if the founders are driven and committed.
So less than 10, it’s too early for me. But after that? That’s enough. That’s where I draw the “post-revenue” line.