As well as turning the characters into plot puppets there’s a risk of turning them into puppets to make a point. One of the main risks of this is putting a point in the mouth of a character who would never make that point. This is risky because we build these characters up and readers feel as if they know them, then if they do something out of character so the writer can make a point it can really disappoint them and spoil a story. It also begs the question, why didn’t we create a character who would make that point?
If we look at the famous scene between Elizabeth and Darcy in Pride and Prejudice where Elizabeth rejects Darcy’s first proposal based on her principles it works because Austen established those are Elizabeth’s principles, this is part of her character. If Elizabeth hadn’t been head strong and determined to make choices based on her own happiness the scene wouldn’t have worked as well. If Austen had created Elizabeth to be more like her friend Charlotte Lucas then the scene wouldn’t have rung true and been as memorable because Charlotte wouldn’t have made the choice to reject Darcy. Charlotte Lucas marries Mr Collins, who she doesn’t particularly like, because marriage was security for women and that was what she desired most of all, and she’d reached a point where she didn’t expect a happy loving marriage. Darcy’s huge fortune makes him the most secure marriage choice possible so Charlotte Lucas would’ve accepted him. Elizabeth would rather risk losing her security than marrying someone she thought she couldn’t be happy with so the scene works. Austen can make a point about marriage (if that was her intention) during the period with both characters because they both follow the natural path of their attitudes rather than the points being shoehorned in.
In Jane Eyre when Jane runs away instead of having an extra martial relationship with Mr Rochester it fits her character. It also fits her character that she should later reject Saint John and eventually return to Mr Rochester. A large part of the story revolves around a young woman making her own decisions in a time when women weren’t expected to and when being a wife or mistress of a rich man could be a career decision. If Charlotte Bronte is trying to make a point she does it without breaking Jane’s character. The reader might say they would’ve stayed with Rochester in an extra martial relationship but it makes sense that when Jane said ‘No, I don’t want to’ she would then act on it. If Jane had stayed, given her principles of right and wrong, it might’ve been a less satisfying story, certainly less powerful.
Perhaps the moral is that if we want to make a point with our story it will be far more powerful if we give that point to a character who would act on it than a character who wouldn’t.