Over-surveying a single person can introduce survey fatigue, which can lower response rates.
From within the setup wizard, you can enable Simple Survey to track when you last sent a survey to a Case Contact, so you can consider it in your Workflow criteria.
The sample Workflow rule provided has a default of 7 days, which can be changed within the rule criteria.
Within the Optional Setup section of the Simple Survey setup wizard, select the checkbox to enable this feature, as shown below. Then click Save.
Note: This feature is only available when sending surveys from the Case object. To avoid survey fatigue with surveys related to other objects, please review this knowledgebase article on Extending Survey Fatigue Trigger to Custom Objects.