and hard drives failed more frequently than today. The biggest problem with recorded video back then was that most set the frame rate for each camera too low (3-5 frames per second) and you could easily miss someone walking out a door or even a car driving by. If you set your frame rate for each camera to 30 frames your digital storage would be used up in no time. The frame rate for each camera had to be programmed individually back then and most set it to the lowest setting instead of using a high frame rate for important cameras. Many a court case got thrown out because of low frame rate video.