How do Transients gradually cause electrical equipment damage and eventually failure?
Transients cause stress to be induced on the electrical grid. Stress causes resistance and excessive heat buildup in electrical equipment. Think of it this way. If you, yourself, are under a lot of stress, what is that doing to your body? It is restricting the blood flow to the rest of your body, or your equipment, and that causes equipment damage and eventually failure. The same is for your electrical system. Transients cause stress, which causes equipment damage, which will eventually lead to equipment failure.