I know - there are things I hate more, but this one bothers me Every*Freaking*Time.
It's the stupid breaking bridge scene in Moria. So, there is a big gap and we have to get over it. A Balrog is behind us. (I'll admit they don't know the bridge will break, but it's something they might have considered...)
Who do we leave for last? The wizard, who might be able to fight the thing? The warrior?
No -- we leave the ringbearer (with ring) and the heir.
Also, I can never see this scene without thinking - Oh, Alan Lee, I love you so! But why did you have to be responsible for this!!! (I said this, almost verbatim, to him at a book signing once, and he just laughed.)
(Of course I have a few *questions* about book Moria as well -- the big one being that Gimli has just told the fellowship that Moria means The Black Pit and was not called that when it was new.
*'Only once before have I seen them from afar in waking life, but I know them and their names, for under them lies Khazad-dûm, the Dwarrowdelf, that is now called the Black Pit, Moria in the Elvish tongue. *
And then Gandalf reads the runes on the door: They say only: The Doors of Durin, Lord of Moria. Speak, friend, and enter. '
So, why does it say Moria on the door? Inquiring minds want to know.....