@Romizabooks - Rewriting a rough draft after a story pitch was accepted used to be a perk accepted authors received if they were taken on by a literary agent and sold to a large publisher such as Hachette, Penguin, Harper Collins, etc. Jean Auel talked about it in a television interview back in the 1980's - I remember watching it, although I don't remember the network. She actually admitted on the air that her writing was terrible, even though her ideas were good, and her background research was strong. I was floored that she would cop to having her assigned editor be a ghost co-author.Back then, there was quite a stigma to using ghost authors or to admitting that you needed help to make your work readable. The public admission didn't hurt her, though.
I've also read that VC Andrews, Anne McCaffrey, and "Carolyn Keene" (a pen name) all used ghost writers to write some or all of their catalog of books.
I don't know if assigned editors will rewrite manuscripts to make them readable today the way they did on the past, though. Now that AI exists, rewriting will probably be a delegated function. What won't change will be the importance of the book pitch. If you want to be accepted by an agent or a publisher, you'll need to sell your book concepts and sell them compellingly.
Good luck!