For me the success of this short is all about the theme of friendship and the surprisingly effective facial expressions that effectively convey the dust bunnies emotions despite fairly minimal animation of these characters.
The music is also quite effective in expressing the emotions of the characters and accentuating the action and tension.
I've seen lots of shorts with better animated visuals but few that have more effectively depicted the characters emotions. Some animated shorts look great but don't convey the emotions as effectively.
There is also very little to the and a really plot but its all carried by the characters expressions and the music.
