This helps add some balance and variety by then making the perfect condition armour and weapons much rarer and giving more reason to actually purchase them off blacksmiths/vendors (I hardly ever bought any unenchanted armour and weapons past the first level). Or if you have the right blacksmithing skill you could 'restore' them to perfect condition using ores, letting them achieve their maximum damage/armour rating.
This way it could be much easier finding a full set of 'rusty' or 'worn' steel armour, but then giving '[censored] yeah!' moments when you find an armour piece or weapon in perfect condition. Plus the rusty, tattered, worn aspect fit in nicely with Skyrims rugged and wild setting.