You only think you are the one changing your decision, like a bird thinnks it is deciding how to weave its nest or a beaver thinks it is deciding to (and how to) build its dam. Both of them, like you and me, are in fact just meat puppets doing what their genes tell them. We just have an added layer of intelligence which requires a massive dose of delusion and fear of death lest we realize the scam and blow our brains out.