A soft bounce refers to a temporary issue that prevents an email from being delivered, such as a full inbox or a server that is temporarily unavailable. In Pardot, when a prospect's email address experiences a soft bounce, it does not result in an immediate invalidation of the email address. Instead, the email can bounce multiple times due to various reasons before being permanently marked as undeliverable.
This means that Pardot will typically keep track of the number of soft bounces over a period. If the email continues to result in soft bounces consistently, the system may take action after a certain threshold is met, potentially marking the email as problematic. This approach allows for a more nuanced understanding of deliverability issues, accommodating situations where the problems may be temporary rather than a reflection of a poor, invalid email address.
In summary, a soft bounce indicates a temporary issue, and it allows for multiple occurrences before any drastic measures are taken regarding the status of the prospect's email address.