Granite countertops might stain, depending on the liquid that is spilled. If the liquid is immediately cleaned up, it is unlikely to stain at all. Water might stain granite temporarily, however, leaving a small dark spot until it dries completely.
True granite stains are caused by materials that do not evaporate, like oils, but remain on the surface of the granite and soak into the stone. Even these stains can be removed from granite countertops using a paste that will draw out the oil. Most granite has a protective coating over the top that inhibits the stone from absorbing materials, but this is not always the case.