Catholics and Christians, repetitive prayer?

I think repetitive prayer is more for yourself rather than GOD. Everyone knows GOD is intelligent and doesn't forget something we've asked of him, but repeating a prayer somehow gives us as an individual mental relief. You know its already in God's hands and timing the minute you ask it but somehow repeating that one thing that really aches your heart is comforting knowing someone of a higher power and intelligence cares and is listening.