The observer effect
In physics, the term observer effect refers to changes that the act of observation will make on the phenomenon being observed. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner.
I think this also applies to education, and I'd love to see some research to support it if anyone knows of any. Anecdotally, I can confirm it in my adult offspring, who were all curious and intrinsically motivated learners as autonomously home educated children, only to completely switch off as soon as the local authority home ed adviser was due to monitor their education, and to stay switched off for about a month afterwards. (I agreed to three annual visits to help my case in ongoing court hearings with my ex-husband, as a result of which the children only wanted to learn for ten months of the year. This was remedied when the visits and the court hearings ceased.)
It wasn't to do with the way I presented the visits to them - I was always positive and upbeat about them. It wasn't anything particular in the attitude of the adviser - she was reasonably non-judgmental and very happy with what we were doing. It was purely and simply the act of being monitored. Judged. Observed. And I know some more sceptical readers might sneer and think: "Poor little flowers! They couldn't stand to be observed? How on earth would they have coped in school?!" Well, they would have coped, I know that. But I don't think they would have wanted to learn very much. (And I think learning and performing are two very different things, like education and training.)
I think I might sort of understand why some local authority officers and governments want to force an annual monitoring scheme on home educators. They mistakenly believe they have, or even want to assume responsibility for the education of all children. Most children's education is delegated to them by parents on a full-time basis, so they think all children's should be. They don't know about the observer effect. They have nothing to measure it against, which is surely the essence of the problem.