* Why Validation Rule?
* Validation rules are efficient for enforcing field-level conditions without requiring Apex or Flow.
* A formula can check if the user's profile is not "Sales Manager" and if the Lost Reason field is blank when Status is set to "Closed Lost".
* Why Not Other Options?
* A: Triggers are more complex and unnecessary for this simple validation.
* C: Record-triggered flows are less efficient for field validations compared to validation rules.
* D: Approval processes do not handle this type of field-level restriction.
* Validation Rule Documentation: https://help.salesforce.com/s/articleView?id=sf.
fields_about_field_validation.htm
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