In the old Taoist texts of Chuang Tsu, there is written one of my favourite parables about a gigantic tree. The tree is massive and thought to be special wood as "those of three or four spans are cut down to make beams for tall, elegant houses. (And) those of seven or eight spans are cut down to make side boards for the coffins of aristocratic and rich merchant families." Such good trees never grow as big as this one, instead, the trees "never achieve their full stature but fall in their prime under the blows of the ax." Even a tree of one span or more is used for monkey perches, it is said. So what kind of special wood is this? What will such a great tree be used to build?
Upon closer inspection, the tree's branches are observed to be gnarled and it's trunk curved and knotted. The wood would not be good enough for beams or rafters. "Indeed, this tree is good for nothing. No wonder it grew so big. That is how it is! Holy men treasure this worthlessness."
This explains the "hazards of being useful."