If you watched a trillion frames of video at 60 frames per second, it’d take you 528 years to view it all (the entire one second of action). Like someone else said, even if you could do it, you probably wouldn’t want to record that much in the first place, because... who’s gonna watch it?
You’re gonna explode your eyeballs!
By having the record one could instruct a computer to go to a specific section and see what is actually recorded, thereby making the speed useful in studying things like cellular processes and molecular reactions.