I am asking this from the point of a reader not a writer and just wondering why, so sorry if this is a bad place.
I read loads of books to my kids and the construct always seems to go:
"what"What a day"day," gleefully burbled Kate
withWith all of the information needed after the fact for reading out loud, so: who is speaking and the mood of the speech.
So why is that preferred over?:
Kate gleefully burbled "what a day"day."
This example is chosen to show a quote which I would read in a gloomy voice to discover I was completely wrong after the fact.