ufo

why is it that most modern day ufo stories do not contain actual video clips with the ability to photograph and/or video with every technology. ie. phones,computers,cameras.etc we have more pictures from old stories befor our current techtnological advances

also, why do we think all ufo sightings have to involve a craft with visable external lights that everyone can see? If the world had that many ufo's actually flying around the airspace then the billions of airtraffic or other radar would pick it up and we would have better proof.j