Why, I don’t get it.

Basically, as much as the magnet on the car is pushing it forward, the magnet on the stick is pulling it back and it doesn’t go anywhere.

It doesn’t work because, while the front magnet is pulling the car magnet forward, the car magnet is also pulling the front magnet backwards and the front magnet is also attached to the car, so it cancels out.

In simplest terms, the two magnets are trying to pull toward each other equally. But when you glue them on the board, that glue holds the magnets apart, and “pushes” them the same amount that the magnets “pull” towards each other, hence no movement.

There would only be a movement if one side was pulling more than the other. The hand is providing that imbalance at first which moved the car.

Its a remote control car

Magnet want to pull and stick to each other of the different pole. When it glued to the car, the one on the cardboard will want to move toward the car and the one on the front hood will want to move toward the cardboard. The force cancel each other out so no movement will happen.

Ok when not glued: both magnets get pulled to each other. The hand has to use some force in order to stay in place, so the car moves.

When glued: both magnets still get pulled to each other, but now the force is cancelled out since the force that would pull it forward also has to be used to hold the other in place.

I think it’s the same as trying to give a sailboat acceleration by trying to blow the sails while standing on deck.