Highly relevant point from Professor Umbridge:
The Ministry for Magic has always considered the education of young witches and wizards to be of vital importance. The rare gifts with which you were born may come to nothing if not nurtured and honed by careful instruction. The ancient skills unique to the wizarding community must be passed down the generations lest we lose them for ever. The treasure trove of magical knowledge amassed by our ancestors must be guarded, replenished and polished by those who have been called to the noble profession of teaching. Every headmaster and headmistress of Hogwarts has brought something new to the weighty task of governing this historic school, and that is as it should be, for without progress there will be stagnation and decay. There again, progress for progress’s sake must be discouraged, for our tried and tested traditions often require no tinkering. A balance, then, between old and new, between permanence and change, between tradition and innovation because some changes will be for the better, while others will come, in the fullness of time, to be recognized as errors of judgement. Meanwhile, some old habits will be retained, and rightly so, whereas others, outmoded and outworn, must be abandoned. Let us move forward, then, into a new era of openness, effectiveness and accountability, intent on preserving what ought to be preserved, perfecting what needs to be perfected, and pruning wherever we find practices that ought to be prohibited.