It's a nice concept, and the execution is roughly decent.
Few things that come to mind are-
1. It needs visual feedback when the ball reaches the target. Maybe make the bin glow/blink, or add some confetti, or something that will be very clear but won't distract the player too much.
2. Set different colours to the UI and the game objects. It took me a while to figure out that the bin thing was the target area for the balls. (Even though I read the description)
Nice work, and good luck!