Coaxial cable is more susceptible to damage when compared with other cable types like category cables and power cables. Your need to understand how coaxial cables are made it order to understand how they can be damaged. Coaxial cables have 4 parts (from the inside out): the inner copper core, insulator, metallic shield, and plastic jacket. There are four things that damage a coaxial cable: physical, water, heat and connector.
Physical damage – coaxial cables should be handled with care. Overly bending and smashing a coaxial cable can cause damage to core which will affect the transmission of a signal.
Water damage – coaxial cables are not waterproof. Water in or on cables can cause changes in video quality. Water can also damage the connectors.
Heat Damage – coaxial cable susceptible to heat damage. The interior insulator can warp causing loss of video quality.
Connector Damage – Connectors can go bad from constant use. The connect itself can be dislodged from the cable. Even oxidation can cause video quality issues.