I mean they're biased in favour of MJ. They're propaganda.
It's alright if you want to just read about how wonderful MJ was every minute of every day, but it isn't realistic. We know that isn't realistic. There isn't a person here who can say they've never been in a bad mood, never thrown a tantrum, never been mean to someone - MJ is no different.
When I read about MJ, I want a realistic version of events, not a glossed over 'MJ was brilliant for every second of his life' pamphlet authorized by the estate.
Take Moonwalk - there are proven lies in Moonwalk. MJ claims that his skin isn't getting lighter, it just looks lighter due to lighting techniques. We now know this was untrue. His skin was getting lighter - he had vitiligo.
So just because something is authorised, that doesn't mean it is true. The estate isn't going to print anything about MJ that doesn't show him as being 100% perfect, but that simply isn't realistic.