Frank Williams, founder of the Williams Formula One team, purportedly used to ask this question of any proposed change or innovation:
Does it make the car go faster?
I love the simplicity of this. It encourages a laser-like focus and chimes with Occam's Razor one of my favourite management heuristics.
Too often in schools, we get distracted by things that don't matter: things that either make no difference to the main effort or that positively detract from it. The recent work I've been doing on Harrow Bangkok's vision and mission has really brought this home to me.
If staff are doing things that don't contribute to the mission, then they should be told/allowed to stop. An educational equivalent of William's aphorism might be:
Does this help children learn?
Apply that question to everything you do in school do and see what you're left with. It's quite a humbling exercise.