I've noticed that the disposable diapers I use on my children have an elastic band around the legs (blue arrow in image below). Sometimes, if care is not taken, the diaper "flap" (red arrow in image below), will be folded inwards, such that the elastic band (blue arrow) is not against the skin. Does it matter if the elastic (blue arrow) is directly against the skin? Should I bother to make sure that the elastic is against the skin? I'd like to see an official reference on whether it matters, since I have a disagreement with my wife regarding the matter.
I assert that care should be taken to ensure the elastic is directly against the skin, whereas my wife thinks it does not matter at all if the diaper "flap" (red arrow) is folded under, such that the elastic is not directly against the skin.