Saw a post on Reddit, and now I have feelings. Allow me to stand on this here soap box for a minute.
JKR has stated that Fred and George figured out the passphrase for the Maurader's Map by being coached through it by the map itself. This makes me all the more irritated with the line "Never trust anything if you can't tell where it keeps its brain" and I absolutely hate that she made Arthur Weasley say it. It's a moment completely out of character for him, a man who offers soft comfort and encouragement to his children every day. A man who only ever raised his voice once in 7 books when his sons took a prank too far and intentionally caused harm. There's no way he would berate his daughter, who is clearly torn up about what happened, for getting manipulated, especially not as the first words he speaks to her after she was minutes away from death.
Inconsistent world building leads to inconsistent characters. It's literally never addressed that the map is sentient, just like the fucking diary. Nope, we're just told talking diary = evil, and dumb Ginny should have known better; meanwhile, talking map = funny and brilliant piece of magic.
Fred and George fucked around with a parchment that coached them how to reveal enchantments on it and nothing happened to them. How the hell was an 11yo girl supposed to assume her talking diary was nefarious??? She lives in a literal world of magic where letters scream at you and mirrors offer encouragement and grooming tips. Why the fuck *wouldn't* a magical diary offer sympathy and soothing words, friendship and camaraderie??
I have to step off this soap box, I could ramble on forever, so I'll part with these words - JKR did Ginny dirty