The one-sentence test
Can a real user complete the single most important workflow, start to finish, without it? If yes, it's not core — it can wait. This single test resolves most scope arguments.
What almost always belongs
- The one core workflow, fully working end to end
- Basic authentication (even single-role)
- Enough data persistence to make the core workflow real, not simulated
What almost always waits
- Billing/subscription infrastructure
- Multiple user roles and admin tooling
- Edge-case handling for rare scenarios
- Polished, fully-branded UI (functional and clear is enough for validation)
Why this discipline matters
Every feature added before validation is a bet made without user data. See How Much Does a SaaS MVP Cost for how directly this scope discipline affects price.
Questions
What if I already know I'll need billing eventually?+
Knowing you'll need it eventually is different from needing it in version one — it can be planned for architecturally without building it yet.
Isn't a narrow MVP a worse first impression?+
For real validation with real users, a working narrow product beats a broad, half-finished one — see What Happens When an AI Automation Fails for the general principle that a working narrow scope beats a broad fragile one.
Who decides what's 'core'?+
Whatever the single most important user action is — decided jointly during scoping, not assumed from a generic template.