Active vs inactive invoices

[Dennis Muhlestein]

I've created, posted, and processed payments for a few invoices.  Is 
there any suggested workflow that says when an Invoice is to be marked 
inactive?  I noticed after I processed the payments that the invoices 
are still active.  Do I have to mark them as inactive manually?  Should 
I ever even worry about marking them as inactive?  Does the 
active/inactive effect anything else besides searching for invoices?

-Dennis