It can't get lost, just because it was never shown in the films. The films can only show/do so much.
So despite discovering self repairing droid technology, teleporters, self learning robots, advanced plasma weapons etc they are still using the same stuff as us in the films?
Either the Empire was penniless in the films and using antique equipment, or stuff has been lost.
This is ignoring the fact that a republic based on democracy is full of unelected officials and that somehow hasn't changed in thousands of years.