What is an example of an activity-based starting point?

Activity-based starting points for automations are triggered by a subscriber's actions or behaviors. "A contact purchasing a product" is an excellent example, as it directly reflects a customer's engagement with your business. Similarly, "The way a contact interacts with the emails you send" (e.g., opening an email, clicking a link) is also activity-based, as it's a direct response to your communication. "A recurring date, like an annual event" and "A specific date, like a contact’s birthday" are both date-based starting points, not activity-based. They trigger based on a calendar event, not a user's direct interaction.