E.g.,

The floating gem operates differently to the ad gem box. The ad gem box adds to the gem count when the animation finishes as the gem floats up and meets the number.

The floating gem works differently and adds it immediately on tap and the animation finishes later. This is important as you don't have the same amount of time to shift your eye to actually witness your gem count increasing in the same way as the ad gem box, so you make think it is not adding to your count when it really is.

Might not be that, but I initially thought the same and then noticed that slight difference, when I stare directly at the total gem count, I see the number go up.