If the component utilizes capacitors in it's circuitry; the better the dielectric material(ie: Teflon/polypropylene/polystyrene), the longer the piece will take to, "break-in." Cables also act, to a degree, as capacitors, with regards to the dielectric/"break-in" ratio. This isn't the only dynamic at work, but has a lot to do with the sound of components changing, over time.
