Here is an explanation of the statuses you will see in the sent emails log.
• Generated - Message has been created
• Processed - Message is ready to be delivered
• Delivered - Message has been successfully delivered to the recipient
• Dropped - Recipient's email server had an issue receiving email
• Deferred - Recipient's email server temporarily rejected message
• Bounce - Receiving server could not or would not accept message
• Open - Recipient opened the email
• Click - Recipient clicked on a link within the message
• Spam Report - Recipient marked message as spam
• Unsubscribe - Recipient clicked on the 'Opt Out of All Emails' link