Are UFO'S spoted or noticed on video cameras around the world that focus on the horizon/shy/ city skyline?

After seeing many pictures on the net of ufo sightings and hearing heeps about reports. Surly then UFO's would have been spotted on professional cameras that are 24 hours focuesd on the sky, for example, weather cameras facing the sky 24 hours a day and night. How come some person accidently snaps a strange object on his camera behind him in the sky but we never see or hear objects that have been captuered by 24 hour running cameras that are facing the sky?