If you use Mail on your iPhone or iPad, then you’ve probably noticed it’s considerably difficult to delete messages — by default, there’s only an Archive button. There is a way, however, to move messages to the trash. It just isn’t very intuitive.
Simply put, most of us don’t want to archive every single email message. In fact, a lot of email messages have no business in our inboxes. But if you go to your mail through “Mailboxes”, Apple has hidden that Delete button away, replacing it with a lonely Archive option:
