How do you know when a side project is actually ready to launch vs. just "done enough"?

I've spent the last couple weeks building a B2B SaaS starter kit solo: auth, multi-tenancy, Row Level Security, the works. Functionally it's solid: I tested every flow, fixed real bugs (including a nasty RLS recursion issue), and it's genuinely useful, not just a demo.

But I keep going back and forth on whether "it works and I'm proud of it" is the same thing as "ready for other people to pay for it." Everything I've read here about cold launches landing with a thud makes me want to slow down and build some real presence first rather than rush to Product Hunt on day one with zero audience.

For people who've shipped something solo before, what was the actual signal that told you it was time, versus just being tempted to launch because you were done building? Was it a specific number of users, a gut feeling, external feedback, something else entirely?