As a librarian, for over 30 years I've used computers to track book circulation and I've learned how foolish it is to hang on to equipment till it fails.  When the computer fails to register that a book was returned, we have back up ways of finding it.  But there's no back up to aging voting equipment.  Voters must have confidence that their vote will not be lost.  The integrity of the vote is the foundation on which the legitimacy of government rests.  Don't put it at risk by failing to replace outdated equipment with new machines that provide a paper trail.