I learned an interesting fact recently (and sorry I don't have the source--it was in a video I was watching over someone's shoulder). There was a educational reform someone was interesting in studying--a new method of teaching. They had several teachers try it out. Luckily they had a person who had been using this method for years to come and observe them. What she observed is that it took the teachers three years to really learn how to do the program correctly. This is something you never year about. It takes new teachers several "survival" years before they can start thriving--even ones who turn out to be great teachers have this period of time where they are swimming with their heads barely above water. This is why teachers don't like reform. Sure this method MAY be better, but experienced teachers are going to have to throw out years of learned skills and TEACH WORSE for two or three years before they start teaching better. If a teacher has to go through this once or twice in their career...they can handle it. But if they are constantly dealing with forced reforms, they are constantly staying in that "survival" mode and never actually getting to the place where they can thrive.
Sure...changes do need to be made sometime. But, I think politicians should avoid forcing reform if possible. Sure, there are some reforms that have to be forced or they don't happen at all (changes to the whole school structure for instance). But even these can be implemented in new school, and shouldn't often be required state/country wide. On reforms that don't require a whole school to be involved, new teachers can be taught these methods at the University (teachers who are learning anyways) and the new techniques will gradually find their way into classrooms without making whole schools full of teachers go through this painful "growth spurt" at once. .