Really fun game loop! I had fun in the tutorial sandbox mode without a timer, sent out several truckloads, then realized I hadn't even started the real game yet haha. I like how each action is a unique mechanic so you're constantly doing something new. I think a few things could be indicated a bit more clearly - like at first I didn't even notice the box pop up on screen to tape it up, and thought I had to click on the small box my character was holding instead. My focus was fixated on the character so I missed the popup since it wasn't glowing or had arrows indicating I should click on it. I figured it out right away, but it took a second, which was a lot of time for the pace of the game! The conveyor belt created a good sense of urgency and frantic speed, which was perfect for the style of gameplay. Music and sound could have really enhanced the mood even further! I think if you want to use the mouse for taping and placing boxes in the truck, it might even be good to use mouse interactions for everything else too - click a box to pick up, some sort of interaction to start the scanner, etc. Right now my mouse hand is idle 50% of the time, then interacting with a small mechanic the other 50%, so it feels like i'm waiting a lot and just playing left-handed, when I think I'd prefer to be constantly anticipating the next task and playing with both hands.
Really nice visual polish, solid framework for the game loop and no major technical issues or bugs. Excellent work!!