I see two big failure states at Montessori schools. The first, and biggest, is constant parental pressure to move away from Montessori and more toward traditio

I see two big failure states at Montessori schools. The first, and biggest, is constant parental pressure to move away from Montessori and more toward traditional education. This is typically because parents don't actually understand or value Montessori, they either want to brag about sending their kid there, or they're simply using it as a preschool with no intention of keeping their kid there after public school options begin. A school without a strong leader at the top will get kicked around by the parents and start to implement weird and non-useful policies and educational choices. The end failure state here is parents on the board, and a school which moves away from Montessori and ends up a middling small private school with nothing to guide its direction. The second, as you're alluding to, is just poor teachers. It's very obvious when you walk into a Montessori classroom if the teacher has control of the class. A good Montessori classroom will have the kids engaged in group projects or quiet individual work, some kids helping other kids or giving lessons, and the teacher simply watching ready to step in if a child needs a lesson or some help moving forward. A poor Montessori classroom will have kids scattered about, chatting with each other, running around or being inappropriately loud, and a teacher haggardly running from problem to problem trying to fix it. The best Montessori teachers know how to give constant joy and encouragement, but also come down like a ton of bricks for misbehavior. But they also need to be able to know each child well. If you don't know the kid, you cannot keep them pointed in the right direction, because each kid is different, and you'll lose them to idleness and lack of motivation.