When mistakes add texture

Even really good writers make mistakes. We forget stuff, don't do enough research, we stumble into inconsistencies we didn't realize we were creating. It can make things tricky when you are trying to consider a story as taking place in its own self-contained world in order to evaluate it. In these instances we are obliged to either dismiss it, or come up with a reason for it, and unpack the implications of its existence.

For example. I've always kind of loved how Alfred consistently addresses Batman as "Master Bruce." It's a charming old-world sort of habit, and as Alfred both has an old-fashioned job being a butler, and is canonically British, we tend to accept it as a character detail. But technically it's not correct for any of those circumstances. If Alfred were behaving according to correct traditional British etiquette, he'd have stopped calling him Master Bruce once he turned eighteen. And as an adult man with a deceased father, he wouldn't have even switched to Mister Bruce but gone straight on to Mister Wayne as head of his family. It's pretty clearly an example of a research fail, of thinking a butler calling his employer "master" just makes some kind of sense.

But in this case, I think you can interpret it as an interesting character statement. Alfred chose not to update his term of address for Batman, and Batman is content with instead being called the same thing he's called him since he was a child. I like to think it comes from an affectionate place, given the paternal relationship he has to Bruce— a subtle statement of "you're my boy, and you'll always be my boy." And for Bruce himself, it's a familiar and comforting throwback to his life before the trauma of his parents' murder. It's also a nod to a slightly sadder truth, that in a way Alfred understands there's a part of him that's stunted at that age, that never grew past being that traumatized eight year old. So it's a little odd and off, but in context it creates some interesting meaning.