That's just the luck of the draw, a factor in both Larian titles. I can't begin to say how annoying it could be in Divine Divinity to come across one of the unique items, only to find that this time the luck of the draw was against me--and it had almost no advantages at all! The best thing to do is save before you run your mouse over the item in question, and discover its properties. That way, if you end up with something hardly worth the battle, you can reload and try again.
