Many Authorization Definitions have the option of using a shelf-life. You set the shelf-life for a definition in the Authorization Definition Dialog using the shown controls:

You may enter a numeric shelf-life between 0 and 9999.  This number is the number of shelf-life days for this definition.

You can turn off the shelf-life feature for a definition by de-selecting the "Enforce Shelf-Life" check box.  Note also that a shelf-life of zero is the same as not using a shelf-life at all.