Big or small, good or bad, there has to be some kind of character development if you want a reader to like your book. There are few things more frustrating than reading a novel and reaching the end to find that the character hasn’t changed in any way. It’s not realistic. It’s not engaging. Very often it makes readers dislike the character in question.
Recently I read a novel where the ‘protagonist’, and I use this term loosely, started off lazy and unlikeable and ended lazy and unlikeable. He went through a harrowing, life changing experience, and he came out of it exactly the same personality wise. I wanted to come through the pages and pummel him. What is the point of a character who doesn’t develop in some way? No amount of plot is going to cover up a lack of development.
Character development doesn’t have to be positive, and it doesn’t have to be dramatic. What counts is that something, in some way, is changing. You have a positive character and they go through an awful ordeal, and in the end they come out bitter? That’s fine. That’s realistic. They reacted to the situation, they were effected by it. Readers want to see that the characters have been impacted by their trials. A good example of this would be to examine a villain. How did they become a villain? Something happened to them and they changed, it may have been negative, but they aren’t the same and that’s what matters.
The same goes for positive character development. Your character should come out of the story with a new mindset, whether it’s an appreciation for something new or an understanding of something old, Want a good example of this? Look at Tolkien’s writing. It’s chock full of character development, some of it minuscule and some of it glaring.
People want to be able to connect with the characters, and if you remove the reality of personal growth through experience, that’s a hard thing to do. There’s a reason heroes and villains get so much attention. They are people who are constantly undergoing development in various ways. If your character isn’t learning something from their experience, then why are they the main character? What’s the point of the plot? Readers need to see the aftereffects. They need to see the emotion. Both require that your character come out different than they started. Character development is essential to the success of any story, don’t toss it aside.