The Picard ManeuverFound this dusty antique from the days when video players would let you buffer. If only this were still a thing.
DreamySweetFor longer videos, a lot of people will stop watching before the video ends. A lot of bandwidth is wasted by buffering the entire video when the user is only going to watch 50% of it. To save bandwidth, sites like YouTube only buffer a tiny bit at a time.
6daemonbagIIRC YouTube breaks the videos up into chunks to achieve that