A sales rep sent out a bunch of Sales Insight emails yesterday. Today, she was following up by phone and found a couple instances where the lead did not receive the email. When I look at the specific records, they show that an MSI email was sent. It also shows that the leads are not unsubscribed, marketing suspended, blacklisted, etc., and the email does not show as a bounce. I can't figure out why they would not have received the email, and don't know what to tell the sales rep.
I know there is always a possibility that the lead could have not looked in their junk folder or could have mistakenly deleted it, but for benefit of the doubt, is there something else I'm not thinking of to explain to the rep why their lead didn't get the email? Any ideas/suggestions?
There are no guarantees on email.
Marketo does not always receive a negative or positive response from the Server. So it marks "non response" as "Delivered". But the target server may have filtered out your email BEFORE it even makes it to the spam folder or the inbox. So yes, some people will have lost the email in that sense.
Nothing to worry about unless you suspect the inbox % is lower than 90%. You can test via 250ok or other tools.