Why filter words matter
Filter words report perception instead of rendering it: “she heard footsteps in the hall” keeps a narrator between the reader and the sound, where “footsteps in the hall” puts the reader right there. Cutting them is the fastest route to deep POV. They're not wrong — but each one is a decision worth making on purpose.
Keeping POV consistent
A “head hop” — slipping into another character's thoughts mid-scene — is one of the most common POV problems. This tool flags mixed person so you can check. (More on the most popular choice in third person limited.) In Muze Writer, the Muse holds your narrator's voice from your Story Core, so its suggestions stay in the right POV.