The magnets will be difficult to explain without polarization of the metal molecules inside of them. From what I remember in school (which is not much), all molecules have charged particles. These are usually balanced out . However, with magnetic compounds the elements have all been forced into a specific confirmation, so that the positive and negative poles are segregated, rather than mixed. Through some sort of voodoo magic this creates a force or magnetic field. However, given enough time and use, magnets can wear out, this is due to the positive and negative elements of the molecules returning to balanced state. So some industrial grade magnets need to be replaced or "recharged".