Neither universally wins; the right choice depends on context.
Waterfall — sequential phases (Discovery -> Build -> Test -> Deploy). Plan everything upfront; deliver at the end.
Pros:
- Predictable budget and timeline (in theory).
- Heavy documentation suits regulated industries.
- Fixed scope = fixed price contracts.
- Clear governance gates.
Cons:
- No course-correction during Build — late stakeholder feedback = expensive rework.
- Long time before users see anything.
- Requirements drift between Discovery and go-live; built solution may be outdated.
Agile — iterative sprints (typically 2 weeks). Ship small increments. Adjust scope based on feedback.
Pros:
- Early and frequent demos = early validation.
- Course-correction is cheap.
- Higher engagement from business users.
- Better adaptation to changing priorities.
Cons:
- Predictability harder — "we'll know what we built when we're done".
- Documentation often lags.
- Fixed-price contracts hard to write against agile delivery.
- Demands disciplined product ownership and stakeholder availability.
Pure Agile rarely fits Salesforce projects because:
- Many Salesforce implementations are upfront integrations (data migration, single-org build) — which are genuinely waterfall-shaped.
- Compliance + audit needs sometimes mandate documentation cadence.
Hybrid (most common in practice):
- Waterfall structure for the big phases — Discovery, then Build, then Test, then Deploy. Each phase has milestones.
- Agile inside Build — sprints, demos, story-based work, retros. Allows course-correction within a phase.
- Documentation maintained continuously — not at end of each phase only.
When to lean waterfall:
- Highly regulated (financial services, healthcare).
- Large, multi-team, multi-vendor.
- Fixed-price contract.
- New tech-illiterate stakeholders.
When to lean agile:
- Small / mid team.
- Mature stakeholders comfortable with iteration.
- Time & materials contract.
- Greenfield with uncertain requirements.
A senior consultant explains the trade-off and recommends the methodology, rather than dogmatically pushing one.