The very word itself comes from the Latin arte, from ars, meaning "Art". It is something valuable, something to be treasured. Something not to be cast away easily.
A magical artifact, even more so. For a thousand years, artifacts have been gifted to those who participate in a Pactio by the spirits of the contract; those who have pledged to protect their Magisters and Magistra. Artifacts are objects of power; the bearers of artifacts are those who shape history.
The powers that artifacts confer on their bearers are a grave responsibility. Wars have been won and lost on account of an artifact. Kingdoms have fallen for the lack of an artifact. It is a gift that ought to be received with utmost respect, care, and veneration.
And then one Haruna Saotome received an artifact. Even the densest, most idiotic spirit of the contract should have been able to see from miles away that this was an extraordinarily terrible idea. One look at her, and you can tell that if she receives any type of power, she'll find a way to misuse it horribly.
But if she didn't, life would be boring, wouldn't it?