These are the three main that is looked for in my entry - Animation (Does it have animation? Is it smooth?) - Art (Is the art fitting for the theme? Does it work well?) - Plot (Is there something important happening? Does it make sense?)
Btw if you're wondering, this is a contest hosted by @superluigi16 -Animation: My lip sinking could be smoother -Art: I used a detailed art style, I guess it kinda works well with the theme -Plot: there isn't really much of a story, I just chose the song coz I liked it