It’s not merely ritual, it’s a form of meditation. Unless you’re five years old you’re not supposed to be asking for Christmas presents, or to win the big game, or even for your cancer to be cured. It’s supposed to help you focus on and reify where you want to be within yourself, as with the Serenity Prayer. It’s phrased as your side of a conversation with a deity because that’s easier for a lot of people to grasp and believe than the idea that an internal conversation with oneself could make any difference, particularly for people who’ve been raised with it, and even more so for people who feel powerless.
There are also theological questions of free will and humility. Just because God knows you’re going to prostrate yourself doesn’t mean you don’t have to actually do it, because you don’t know that He knows that, because you’re not omniscient one.
