In Order Rules Triggers is a check box called "Inverted". The purpose of this is to reverse the logic of the Trigger or Result.
Typically, when the criteria for a Trigger is met, the output for the Trigger is set to True (not met = False). When all the Triggers are "True", the Results are applied. If the "Inverted" box is checked, then the output is reversed for that trigger. Example: Say you wanted a Result applied if the Ship Via Code was anything except UPS Ground. You would set the trigger to Ship Via Code = UPS Ground and then check the inverted box. Now the Trigger output is True unless UPS Ground is selected as the Ship Via.