It is very easy to lie down on the correct side when going to sleep. It is not so easy to ensure that one remains on the correct side WHILE asleep.
Holding a coffee cup full of warm salt water to the side of one's head as instructed to do by one's piercer if one happens to have inadvertenty irritated a fresh ear piercing (or two) by sleeping on it is an acquired skill.
Quantity of salt water in cup when first pressed to head to submerge ear: 1 cup. Quantity remaining when finally removed: 1/2 cup. Location(s) of missing water: hair, neck, shoulders, bathrobe, chair, floor, cat.
Water in ears is not fun. Water in ears when a fresh tragus piercing prevents one from doing anything to remove said water is even less fun.
Despite all that, I still like my new piercings. :-)