Let's say you were making a sand and water mixture.
And you said you wanted it "sandier." That would mean to add more sand.
And if you wanted it "waterier" then you'd add more water.
So John's in the shower. The water is one and spraying on him. (I had checked it -- it was warm, not hot.)
He said it wanted it "warmer" so I turned it a bit hotter (continued to check it -- still not hot). He said "warmer", so I turned it a bit hotter and asked if that was OK and it said, "No, warmer!".
I realized what he meant -- he wanted it closer to "warm" further from "hot".