This is a question that has often baffled me. And it's not a trivial question. If you and your potential editor don’t agree on what good characterization is, then the relationship ends before it begins with the manuscript in the discard pile.
I have my own ideas about characterization. I like to see emotional depth, what matters to the character, some idea of what their personality is like and how they might go about getting what they want or overcoming their problem, all blended with the right amount of backstory. All this is best revealed gradually through the actions of the character and the events of the plot.
But for me this stuff is ‘internal’.
For others good characterization is ‘external’. They like to see particular actions or mannerisms in a character that can be readily recognized – and are often repeated ad nauseum through the story. From Harry Potter think of Hermione Granger’s ‘bushy hair’ or Hagrid’s large bulk. It seems like every single time these characters appear there is a reference to the 'key characteristic'. If I read another dark fantasy character who can't be separated from their cigarette, I think I'll choke. If subtle enough, I guess it works as a subconscious cue.
One of the reasons I stopped reading the Wheel of Time series was I got so sick of this. How many times can Nynaeve al’Meara pull her damn braid? Especially when nothing else was happening except a self-perpetuating word-mill of dialogue? I’d rather know more about what makes her tick.
I think a little bit of the external things can be an excellent part of the mix, but when this is supplied as the major component of characterization I start to get annoyed.
There is a lot in this though – it really appears to be a divide in the way writers approach the work (and how editors interpret it). Maybe its even deeper than that, maybe it’s a personality divide.
I was watching a local television program – the Tuesday Book Club – where various local literary luminaries wax lyrical about three or four books, each giving their considered opinion. Even these quite established and successful writers could not agree on this one. One of them was seriously bagging one of the books, criticizing what, in his opinion, was a very superficial characterization for the above reasons, while another could not give it higher praise in the same arena.
What’s going on? Please enlighten me!