What is the purpose of the Clean-up Rule?

The purpose of the Clean-up Rule is to log all traffic that is not explicitly allowed or denied in the Rule Base78. The Clean-up Rule is the last rule in the rulebase and is used to drop and log explicitly unmatched traffic97. To improve the rulebase performance, noise traffic that is logged in the Clean-up rule should be included in the Noise rule so it is matched and dropped higher up in the rulebase8. The other options are not valid purposes of the Clean-up Rule.

References: Using Intune device cleanup rules, Security policy fundamentals, Support, Support Requests, Training, Documentation, and Knowledge base for Check Point products and services