It's odd because many times drummers make the best arrangers.
Bass players and drummers always seem to write really boring music, and I think it's because we are stuck thinking about rhythms, rather than melody. The music is usually complicated, and interesting, but there's no hook or melody line that pulls you into it. No one's sitting around tapping their feet or humming these songs.
To expand on it, I'd put many of the guitar virtuoso types in this category as well. Steve Vai songs, for example, are boring as hell! Much like drummers, and bass players, these songs are complicated, but are usually just a vehicle for someone to shred their chops over.