Most people have some rules in place to automatically move certain emails, they consider as Spam, to a different folder or even to move them directly to the deleted items folder.
However, not all emails that should be deleted have a clear signature for which a rule can be set up. Sometimes long email chains develop that have no relevance for a certain recipient so without a rule they might choose to manually delete every instance of the email. Luckily, Outlook provides a way to automatically move all future messages which contain the same subject as the email in question directly to the “to be deleted” folder.
To do this, right click the relevant message and select the “Ignore” option.