Videos ... like music & pictures ... re-saving into lossy formats means loss of quality enjoyment. It's like taking a digital photo, saving it as a quality 3 or 4 JPG. Then opening that JPG file & saving it at the same quality setting. Open it & look at the image & tell us how it compares to the original. You'd find artifacts introduced into the image, blurring, loss of clarity of original colours, loss of definition, etc. The same applies if you save an mp3 as another mp3. The loss of course for music is the audio attributes such as colour, frequency range & balance, etc. - Like taking a cheap b/w photocopy lol Just IMHO

BTW some people share movies as 2 or 3 x 600 to 800 MB files.