Well, jpeg is a known picture format, and it’s usually able to to acheive a 10:1 ratio. With the ability to allow the user to chose between a mix of Quality vs size.
Though for clips wouldn’t apng work a bit better?
It allows for quality along with video to remain video other than video turned into pictures.
IE I could have a video of the John F. Kennedy Assassination as apng so it would be decent quality and a video format that is compatible with most browsers and operating systems that can open a standard .png file.
Or, I could have it in pictures which would be scrolled across. This would be .jpg (Jpeg).
Seems most would go for the .apng. As it’s video.
That’s the pros and cons.
jpeg = picture format and not video. And it has great quality but as you raise said quality you also gain in size. 
where I work, the media library (roughly a few thousand movie clips) are all conformed too ntsc photo jpegs. Can anybody tell me the pros and cons of photo jpeg as a video codec? It seems rather random to me.
thanks