Yeah, that's the main principle of finding stuff - nobody's ever looked before. Full stop. Though when you do find something it's apt to be dismissed with the argument - not always voiced - "There can't be anything there as someone would have already found it". I can't understand how a young farmer that has grown up herding sheep on a hill, with his dad and uncle, can say about a six foot tall, broad, standing stone - "I didn't know it was there".