AI coding assistants do not automatically apply security best practices. We regularly audit prototypes with API keys in frontend bundles, admin routes without role checks, and SQL built from string concatenation. None of that shows up in a demo video.
Maintenance cost is the other bill. Vibe-coded repos tend to duplicate logic, skip tests, and mix concerns — UI, business rules, and data access in the same file. When you hire your second engineer, velocity drops while they map the chaos.
Production habits are not optional for MVPs that handle money or personal data: environment-based secrets, server-side validation, audit logs for admin actions, and dependency updates on a schedule. These add days, not months.
We are not anti-AI. We use it internally. We also review every generated path before it merges — same bar as hand-written code. Founders who skip that step often pay twice: once for the fast MVP, again for the hardening sprint.