Do you know why certain magnets are called permanent magnets? You don't draw the magnetism out of them. The machine did not slow down because the magnetism drained out. There is a property of magnetic materials called coerciveity. It is the property that determines how hard it is to switch the magnetic field in the material. Another way of thinking of it is the property that determines how hard it is to demagnetize a material. Learn more about magnetsim in general here: http://www.sciencetech.technomuses.ca/e ... agnets.cfm
And here you can learrn a bit about coerciveity: http://www.magnetsource.com/Solutions_P ... erial.html
There is no perpetual motion in the universe, either, it just slows down at a scale far greater than most humans can comprehend.
And no, all magnets do not eventually lose their, "force." if nothing changed their magnetic structure (heat does it for almost all permanent magnets, but that is around the point the metal turns red before it changes the magnetism) they remain magnetic. There are many permanent magnet motors that still work fine many decades later. Magnetism doesn't ,"drain out." There are magnets that are hundreds of years old that are still magnetic.