As you might expect, handling email bounces and subscriber statuses is a complicated balancing act undertaken by email service providers like Salesforce Marketing Cloud. Hard bounces, soft bounces, held status, unsubscribed, undeliverable — what do these really mean?
First of all, it means that subscriber statuses are not simply active or unsubscribed, which is sometimes difficult to explain to marketers — especially when they are scrutinizing subscriber reporting and statistics. There are a couple of pages that on the Salesforce Marketing Cloud help site that outline their bounce management process. The one that I’ve found most helpful is this one:
Keep in mind that there are different kinds of unsubscribes:
Here is more info on that.