Build a Better Filter
New rules are created by clicking the Add button in the Rules window. There are three elements to each new rule: its name, what it looks for, and what it does. Make the name something memorable so you know what the rule does, and if you like, add something about what the filter does; for example, "Sally Schultz (to PR mailbox)". The second part of the rule is entered next, and this is set to include one or more search criteria that Mail will check against all incoming messages. If these criteria are met, the third part of the rule comes into play, and the message is processed as configured. Unless told otherwise, all rules are applied to all incoming messages.
This can end up causing conflicts when one rule is overruled by another one later on in the chain. To prevent this, you need to add the Stop Evaluating Rules command. This tells Mail that once a rule has been triggered by a particular message, that message should be processed according to that rule and then left alone. While testing out new rules, mark messages as Unread (Command+Shift+U) so you can see where they’re moved to, and studiously avoid the Delete Message command. Far better to move messages to the Trash folder—from which you can pull them back if you want—than to delete them. Once deleted, that message is gone!
Figure 3 Use the Stop Evaluating Rules command to keep your filters playing nicely together.