For handguns, I clean them every time I shoot them. The autos get a complete breakdown, but not the revolver. Gunpowder is corrosive, and my autos are a lot smoother functioning if I keep them clean.
My .45 CCW gun gets carried almost 24/7, so it gets wiped down and re-lubed every couple of weeks, and a breakdown if it's real dirty. It's easy for grit to accumulate in the action in this climate. I may be excessive, but since I rely on it, it's staying in good working order.
For rifes, the action gets cleaned after shooting. I've backed off cleaning the barrels as often; a lot of opinions on whether it's good for the bore. So I do a visual check, and occasionally run a rag through them, and they stay accurate.