[Salesforce Specific]
What happens automatically?
If an Opportunity is moved to "Closed Won" and the Close Date is in the past, the Close Date automatically updates to today's date.
Adding automation to update Close Date
Depending on how your business manages Close Date, you may want to add supplementary automation to update Close Date under additional circumstances.
Examples:
Close Lost Opps: Update the Close Date to be today when any Opportunity is lost.
Close Won Opps: Update the Close Date each time an Opportunity is Closed Won, either to today's date or a date field populated with the Contract signature date.
Criteria:
Conditions: If 'Closed' ('Is Closed') equals TRUE
Advanced: Check the box to indicate that that specific change should trigger the automation
Action:
Update the field "Close Date" using the formula 'TODAY()' (or reference whatever field might be relevant)