Lovely little arcade. Reminded me of Rhythm Heaven a bit.
Nice idea to have a live reaction, it was fun to see it changing!
At some point it speeds up so much that all your attention is kept on the conveyor belt. Animations struggle to keep up with that speed, and so do I. Maybe a little occasional break would help to figure out what's going on and to check your status.
I can see the bad ending, but is there a good one? (I guess the good ending is that workers never stop working :3)
The graphics and sounds are great, good job!
Also, a small note for future games: please take care of different screen sizes (quick check: resize your browser window).