Dither isn't all that obvious. You kind of have to listen carefully to fade outs at very high SPL volume to notice it. When you truncate 8 bits from 24 to 16 bits, as you usually do in CD mastering, you automatically apply very unpleasant noise and riples to the premaster. By dithering as the last proces before the conversion you instead apply a pleasant psykoacoustic noise that to the ear actually keeps a pseudo 24 bit resolution in the lower levels in 16 bit! Generally it's fair to say that what you gain in dithering is a more varm and pleasant sound in contrary to a harsh cold sound, we remember from the early days of the digital era where dithering wasn't used as much.