How well do you know the characters in your book?
Yes, you will give the readers a physical description as well as mental and emotional attributes. Well, hopefully, you do.
But how well do you know your character inside and out? If someone asked you about them, would you be able to answer them satisfactorily?
Creating characters in our books is not as simple as throwing lines against a wall and see how many, if any, will stick. We, as readers, need to be invested in them to keep the pages turning.
Creating personalities in one’s manuscript is part of being a writer. The better you are in tune with your characters, the better read it will be
I tend to talk to my characters as if they are real. I have conversations going back and forth, which map out things I might not have thought of before. It is odd, and I suggest you don’t do this in public but getting a good grasp of this imaginary human is vital. And unless you take the time to do this right, one can’t be surprised if people turn on the very same characters you say you love.