For example:
If you pick up a steel sword it could have mud on it or glitches or look used etc.. But If you would pick up the same sword in another dungeon, maybe it has also all the mud on it and the used look as the other sword, but then it should have other carvings or engravings or another handle, or the material is rusted or looks slightly different. I think this could easily be achieved by different shaders etc. and it adds A LOT to the experience as every item looks different. Depending on the look of the weapon you could also draw conclusion on the weapons conditions etc.. Maybe therefore you don't neccessarily need a scale for the condition of a weapon?
ANOTHER REMARK: Maybe Bethesde should introduce towels in Skyrim, so that you can clean and polish your weapon make it look better. It would also come in handy If it would be possible to sharpen your weapon when your PC has a good forging skill, therefore there should be sharpening stones available.
Just my two cents regarding weapons...