@Sal and Lucy and Angle...
And there-in lies a significant difference between some readers and writers.
There are fans who are only fans of one specific character. Regardless of who else is in the book they're only there for that one character.
We know their point of origin. How many books they've appeared in. The stories in which they're featured...
Writers, even if they have their personal favourites, have to write from the perspective of being fans of a significant portion of the franchise if not the entire franchise, itself. They're scope of knowledge has to go beyond that one character and they will miss things that we as individual readers may think is important...it happens.
While some readers are laser-focused on just their one favourite character, writers don't have that privilege. (Yes I am fully aware of the detractions made towards Duggan and Marauders...which I can understand, but with which I also don't agree)
We can be fans of one character and be disappointed with how that character is being presented, but then in the same book, other fan-faves might be written to another reader's delight and expectations...that's just the nature of the product. And if you are only a fan of that one character, chances are you are going to be disappointed more often than delighted.