Miracles seem to be branded out of an act of selfishness. In essence, miracles are things we can not humanly control or produce at will. Unexplained healing is a miracle. Sunsets are a miracle. Gestation is a miracle (we can be vessels of this, but we do not control what goes on inside). Life is a miracle; we live it, but we do not write our DNA, we do not make our bones grow, our hair, develop our capacity for thought and our abilities for caring.
So miracles are events that we are not capable of doing at will. It's outside of our scope; somewhere in nature; super nature!
This is a selfish thought. If we, rulers of the universe, can not do something at will, it must be supernatural. It must only be accomplished by that one, necessary existence right above us...and only that one. There are no more existences because perhaps our pride couldn't handle if there were a super-supernatural. We just need the supernatural to explain why we can't do everything.
It is a very big (read: divine) deal if we are not able to accomplish something. It must be! To call something a miracle is almost the same as saying, "That's not fair! I can't do that!"