If you are right handed, the thimble on your index finger is what brings the needle back up after you graze the underneath finger. That I why I use a thimble with the little edge around the top so when you rock the thimble down, the needle stays in position. ....and unless you are a hand quilter you have no idea what I am talking about.
Do you like how I said graze the underneath finger when in actual fact mine gets sore from all the poking?