This product is designed in such a way that one has to hold the bottle/ glass in his or her hands always while filling water.
This water purifier model is a popular one in companies. Here the user will fill more than one liter of water and this filling procedure may take more than one minute.
But the disadvantage is, all the while one has to hold the bottle, otherwise it will loose balance and water will spill over. Thanks to the slope, it is provided for easy drainage of water. Apart from keeping the user engaged throughout this procedure, the slope is not serving any suppose.