He often causes the gods terrible problems, and just as often solves those problems with his schemes

 --- A description of Loki, from Snorri Sturluson's Prose Edda; given by Jackson Crawford in his Norse Mythology for The Great Courses, lecture 7, "Loki and his Children"

From Crawford's course notes (I don't know which translation he's using; it may be his own)

One is counted among the Aesir gods, who is called by some “the slanderer of the gods” or “the first maker of lies” or “the blemish on all the gods and all humankind.” … He is handsome in appearance, evil in disposition, and extremely changeable in mood. Before all others, he is the champion of the kind of wisdom that is deceit, and he uses lies for all his purposes. He often causes the gods terrible problems, and just as often solves those problems with his schemes.

From the Gylfaginning, translated by Arthur Gilchrist Brodeur (1916)

XXXIII. “Also numbered among the Æsir is he whom some call the mischief-monger of the Æsir, and the first father of falsehoods, and blemish of all gods and men: he is named Loki or Loptr, son of Fárbauti the giant; his mother was Laufey or Nál; his brothers are Býleistr and Helblindi. Loki is beautiful and comely to look upon, evil in spirit., very fickle in habit. He surpassed other men in that wisdom which is called ‘sleight,’ and had artifices for all occasions; he would ever bring the Æsir into great hardships, and then get them out with crafty counsel. His wife was called Sigyn, their son Nari or Narfi.

For comparison, this from Niel Gaiman's Norse Mythology (2017)

Loki is very handsome. He is plausible, convincing, likable, and far and away the most wily, subtle, and shrewd of all the inhabitants of Asgard. It is a pity, then, that there is so much darkness inside him: so much anger, so much envy, so much lust. . . . Loki is the son of Laufey, who was also known as Nal, or needle, because she was slim and beautiful and sharp. His father was said to be Farbauti, a giant; his name means "he who strikes dangerous blows," and Farbauti was as dangerous as his name. . . He is tolerated by the gods, perhaps because his stratagems and plans save them as often as they get them into trouble. 

Loki makes the world more interesting but less safe. He is the father of monsters, the author of woes, the sly god.

it is not irrational for an administrator to defend a policy as good without being able to specify what it is good for

 --- Charles Lindblom, The Science of “Muddling Through.” Public Administration Review, 19(2), 79–88, 1959. https://doi.org/10.2307/973677 (h/t Dale Hatfield)

In context

Agreement on policy thus becomes the only practicable test of the policy's correctness. And for one administrator to seek to win the other over to agreement on ends as well would accomplish nothing and create quite unnecessary controversy.

If agreement directly on policy as a test for "best" policy seems a poor substitute for testing the policy against its objectives, it ought to be remembered that objectives themselves have no ultimate validity other than they are agreed upon. Hence agreement is the test of "best" policy in both methods. But where the root method requires agreement on what elements in the decision constitute objectives and on which of these objectives should be sought, the branch method falls back on agreement wherever it can be found.

In an important sense, therefore, it is not irrational for an administrator to defend a policy as good without being able to specify what it is good for.