If you have minor children you should consider choosing both temporary and permanent Guardian(s).
A temporary Guardian is usually someone who lives nearby. They can spring into action if you are immediately unavailable. Imagine, for example, the following possible scenario: you go out for dinner but don’t make it back home due to a car accident. You may have already named a permanent Guardian for your kids, but what happens to your kids that night? Or, for that matter, what happens to them until the court hearing to name the permanent Guardian? A temporary Guardian is chosen to minimize disruption in your children’s lives, and keep them out of child protective services until a long-term Guardian can be named.
A permanent Guardian is someone that is appointed by a court to care for your children on a long-term basis. This person may live further away, but they have been chosen (by you and/or just the state) as the individual(s) who are best able to raise your kids.