I've read prior discussions on this topic, but I can't for the life of me figure this out.
Their are 14k leads in a stream in an engagement program. An email went out yesterday, and only 500 received it. No one is marketing suspended. Only around 50 are unsubscribed. Only 2 people have no email address. Around 1500 emails are invalid. I'm lost as to why the rest were not included. Does anyone have additional ideas? Thanks!