I get it. Characters change over the course of a novel. On an emotional level, the characters you start with may be completely different by the end of the story. As a copy editor who works closely with independent publishers, the issue I see is that characters sometimes change nicknames, eye color, or other physical characteristics throughout the course of the story. That is a huge potential problem.
Writing a novel takes a long time. Even consecutive chapters may be written several months apart. When you’re writing an important scene in chapter 31, you don’t want to have to go back through the first several chapters to look up whether or not the childhood neighbor (who has suddenly resurfaced) had a mustache. So let’s say you put one in, having the main character recall something about how it bristled, and this memory is an extremely important key to solving a decades-long mystery.
Read the rest of this article I contributed to the WOW! Women on Writing Newsletter.
My essay, 
My article, 