increased Elemental Damage with Attacks vs increased Physical Damage

why is the mod with physical damage with accuracy more highly sought than increased elemental damage with attacks for a weapon like bow? aren't they essentially the same? I even think that the elemental damage gives more value or am i wrong about this? bow users usually uses attack skills anyway so I dont see the "with attack" as a problem. is accuracy that big of a difference? can anyone explain?

one is a local mod, other is global. the local mod scales with all other global mods you have so is much better.