Continuity mistake: In the 8th episode of season 11, "Murder Most Maris", Frasier claims to have been "punched in the face yesterday by a man now dead". When he says this, two nights have passed since the murder. The next day Niles panics at the café and then sleeps for 20 hours. This time Frasier claims he was punched in the face three days ago by a man now dead, when by now it has been at least four days.
Continuity mistake: Roz comes back to the restaurant table, after phoning her babysitter, and says, "I have to go". At this point her purse is over her wrist. As she finishes saying, "Alice got a bead up her nose", she is holding the purse by its strap. A few shots later it is over her wrist again, even though she never moved it.
Continuity mistake: Frasier is off to find Niles and he tells Martin to come with him. Marty puts his chair down as he says "I don't want to go to Niles'" - the shot changes and we see him lower the chair again. His coat in his lap also changes position between these two shots. (00:17:40)
Continuity mistake: Marie and Frasier are sitting on the couch when Marty comes home, and her arms noticeably change position as the shot changes. Then, a few shots later, she has her hands on her legs above her knees, but in one quick shot her hands are wrapped around her knees - without enough time for her to have changed naturally.
Continuity mistake: Roz is at Daphne's shower, saying "God, he sounds just like a prince," in reference to Simon - in her left hand is a drink and her right hand is positioned down, as though it is in her pocket. In the next shot she is still holding her drink in her left hand, but is giving Daphne a drink with her right hand - it just appears out of nowhere.
Continuity mistake: Frasier comes home to find his sherry decanter empty and opens a bottle of wine, which he leaves on the kitchen counter. Niles arrives, wants sherry, and Frasier tells him there is none, saying, "I've opened some wine, help yourself." Niles grabsthe open bottle from the bar area, even though no one had put the bottle back - it should have still been on the kitchen counter.
Continuity mistake: Frasier and Niles are looking at the salt server Blaine returned to Frasier - in one shot the large envelope, the mailer strip, and the note are on the coffee table - in the next shot the strip has disappeared and the envelope and note have changed position.