Fidelity is the total quality of an experience, including a sense of exclusiveness and aura. Convenience is simply how easy something is to get, which often means a low price and ubiquitousness. A super-fidelity product or service would lose its luster and quality if it's pushed too hard toward convenience. A super-convenient product or service would start to get expensive and exclusive if it moved toward higher fidelity, which would naturally undermine its convenience.