What a facilitator does:

Moderates the discussion by managing the method of the meeting, not the content
Ensures the day's agenda is covered to the stakeholders’ satisfaction
Intervenes if the discussion starts to fragment
Identifies dysfunctional behavior and intervening as needed
Preventes dominance and includes everyone in the conversation
Processes misperceptions and emotional reactions
Extracts as much qualitative data as possible out of all attendees
Enables a productive exchange, be it to share points of view, elicit feedback, reach consensus, or develop future requirements
Brings closure to a meeting and ensures actionable takeaways at day's end