Can some one explain to me why this weapon scales primarily with Dex instead of Strength?

I've been using the standard Great-Axe for the majority of the base game and I wanted to try out a new weapon for the DLC, and since I enjoyed using the Great-Axe I thought that I would use a Colossal variant of it. So I did the grinding and finally got the weapon only to find out that is has an A scaling for dex while Strength (which is my build btw) is only a B ranking. It just seems very dumb to me that a Colossal weapon would scale more with Dex instead of Strength.