From my perspective, the argument for the existence of a god has always had one fatal flaw: in all of our human discoveries that were once attributed to a god or gods, none of them actually required a god to make them happen.
Is it possible that there is some kind of being that created our reality? Sure. But how do we recognize that? Where are the moments that only a god could accomplish? If we want to prove that God was responsible for an event, we must first consider if the event could happen without a god. Every time I have looked at a question from that perspective, no gods were required. That is why I do not believe.