To be fair (while much of the writing is definitely shitty) they wanted to keep him in the school non-stop at this point because the people out to get him were becoming more prevalent and his enemies more powerful. So the intention to keep him safe.
But she probably could have directly said that. Most of the problems in the book could have been solved or entirely avoided if Harry would have listened to what he was told by Dumbledore and others
Lmao truly though. I read these books again when I was much older and was just consistently pissed off at him lol. I know he was a kid but holy hell lol. He got a lot of people unnecessarily killed even