Copper cables can experience signal degradation over long distances, which can cause data loss or errors. Despite being made of glass, fiber optic cables are more durable than their copper counterparts too. Susceptible to EMI: Copper is more susceptible to electromagnetic interference (EMI) than fiber optic cables. They offer greater performance, with much higher. Copper has substantial disadvantages over fiber optic cable and, while copper remains very important, if not dominant, fiber optic systems are taking over, leaving copper in a poor position due to its many disadvantages.