Oh well, that's something I honestly didn't know was done...to lather up and manufacture the finished product in the same container as the puck. I'd imagined that the continuous whipping up with the brush on the surface of the puck in order to get the required lather would use up loads and loads of soap rather than just take what you needed and transfer it to the bowl and lather it there. I guess it's good practice to rinse the thing out afterwards as you would the the conventional (empty) lathering bowl?