When should a vibe-coded app stop being treated like a prototype?

Vibe coding is amazing for getting from idea to working demo fast.

But I think there is a tricky moment after the demo starts feeling real.

The UI works. The auth flow seems fine. Maybe payments, webhooks, user data, background jobs, or database rules start getting added. At that point, the question changes from “can AI build this?” to “can I safely maintain and trust this?”

I feel a lot of projects get stuck in the middle too useful to throw away, but not reviewed enough to feel production-ready.

For people building with vibe coding, when do you decide a project needs a proper engineering pass before real users depend on it?