I found this photo on Wikipedia. It provides a good reference. The tapes are pointing correctly, however notice the tension from the top two tapes is applied above the level of the absorbent material. This might be from the design of the diaper but it is better to have the tension applied below the top of the absorbent material so the absorbent material will create a dam or barrier where the fluid is wicked up from the skin.
The method used in the diaper in this linked photo will work well during the day, when the patient is vertical. However it is likely to cause leaks at the top if the patient is laying down. By applying the tension above the absorbent material a gap is allowed and fluid is likely to flood the top. Since the diaper doesn't have the ability to absorb fluids where the contact is made anything more than a small amount of fluid will likely escape the top, even though it has been pulled tight it is not water tight and over time will stretch creating a gap. Referencing the diaper in the photo: It would be better, esp for males, to pull the diaper toward the front so the top of the absorbent material is above the top tapes.
http://fr.wikipedia.org/wiki/Fichier:Tena1_jpg.jpg