Final answer:
In a Smart Campaign, the frequency with which a lead runs through the Flow steps is controlled by the Qualification rules. These rules specifically govern the re-entry conditions and frequency for leads in the campaign.
Step-by-step explanation:
The question pertains to lead management in marketing automation systems. Specifically, within a Smart Campaign, the number of times a lead runs through the Flow steps is defined by Qualification rules. These rules are settings that determine how often a lead can enter the Smart Campaign flow to receive the designated marketing actions. In contrast, Smart Lists define the leads that match certain criteria for the campaign, Auto Assignment rules automate lead distribution among team members or territories, and Membership status might restrict or allow campaign flow entry based on whether a lead is part of a list or initiative but does not directly control the frequency of flow execution.