The lovely Miss Overmore is also lovable at first. But by the end of James's novel, she undergoes a transformation: from well-meaning but shallow to clingy and manipulative. By the time she's sidelined, the reader is likely to think, "Good riddance to whiny rubbish."
When she enters Maisie's life, Miss Overmore strikes the little girl as remarkable because of her elegance and refinement. And sure enough, she's a whole lot classier than Mrs. Wix. She's better educated and has much finer manners. And don't even get us started on the difference between the two women's clothes. Miss Overmore is a hottie with a body and a wardrobe to match.
But James thinks that appearances like these can be dangerously deceiving. And so part of Maisie's quest involves learning to recognize that manners and good looks only get you so far. These aren't nearly as important as the qualities that count, qualities that Mrs. Wix has in abundance: loyalty, responsibility, compassion, and care.
Only gradually does Mrs. Beale prove that she doesn't have quite enough of these traits, and her limitations are likely to be something that the reader sees before Maisie can. (Remember, Maisie remains very young throughout the novel.)
Oh, and since you were probably wondering: no, we have no idea why Miss Overmore becomes Mrs. Beale. That's like a woman marrying a dude named Bob Smith and calling herself Mrs. Bob.
Let us explain what we mean: it's pretty shady that Mrs. Beale, having first worked for Maisie's mother, goes off and starts working for her father and then shacks up with Mr. Farange. That's like leaving, oh, Apple for Microsoft and then having an affair with Bill Gates.
But as if this isn't shady enough already, Mrs. Beale begins an affair with Maisie's stepfather. We can't even come up with a dandy corporate metaphor to describe how messed-up and semi-incestuous this is, especially by Victorian standards.
James expects his readers to share the view that adultery is wrong and that deceit like the kind Mrs. Beale keeps practicing adds insult to injury. So even though Mrs. Beale is consistently kind to Maisie, James wants his readers to see through this kindness as Maisie learns, little by little, that there's more to parental protection and family love than kisses, kind words, and fancy clothes.
So when, in the book's very last scene, Mrs. Beale lashes out at little Maisie, calling her all kinds of awful names, we catch a glimpse of the lady's inner ugliness, and this confirms that her beauty, unlike Mrs. Wix's, really is only skin deep.