The Swordbearer (1982) by Glen Cook is the dark fantasy version of a YA novel. If you know Glen's writing style, you'll recognize the disaster about to unfold. Unlike most YA novel, this one gets the inherent fantasy of boys and young men to murderously destroy all their opponents through powerful weapons and getting all the power.
The book itself progresses well enough until the middle, where the story bogs down and becomes just as series of events. Despite all the battles and all the addition of more powerful magic equipment, all momentum is lost. The powerful magic items becomes meaningless. The conflict becomes meaningless. Even our hero becomes meaningless. (In fact, the conflict is meaningless, which only adds to the meaninglessness that already exists.)
While this story is an interesting direction to take the unwilling hero story, it's a direction that shouldn't be repeated. It's a mediocre tale, one filled with themes that will to on to make his Dread Empire and Black Company stories ring like steel.