Deliberate mistake: In the pilot episode, "The Good Son," Frasier has a telescope which is seen on his balcony. The telescope disappears for the next 3 episodes but in Ep. 5, Frasier gives his father a telescope as a gift. It remains as a prop for many seasons.
Continuity mistake: As Catherine is about to leave Frasier's apartment near the end of the episode, you can see the white shirt she is wearing constantly changes between shots. At times it is hanging out very loosely and in other shots it is neatly tucked in and positioned to the right.
Continuity mistake: When Daphne is setting up the soft ornaments along the top of the fireplace for the Christmas photo, she is just putting the first one on the mantelpiece, then the shot changes and she is positioning the second ornament.
Continuity mistake: When Katherine confronts Frasier in the hall at KACL, her purse strap is over her forearm. But when the shot goes to Frasier, from behind her, the strap is over her shoulder.
Continuity mistake: Near the start of the show, Roz is in her booth at KACL and takes out her lipstick and compact - we see her uncap the lipstick. Then Niles comes in an Frasier reintroduces them, and we see her uncap the lipstick again.
Continuity mistake: Frasier is at the dining room table with Niles looking at Niles's childhood journal. He has his left hand ready to turn a page but in the next shot his hand is on the table, with no time for a natural shift.
Selling Out - S1-E9
Continuity mistake: Frasier meets Bebe for the first time in the hall at KACL. She has her business card in her hand for part of the scene but after Frasier tells her he has a son, the card disappears - with no time for Bebe to have put it back in her purse.
Selling Out - S1-E9
Continuity mistake: When Frasier and Niles are in the Cafe, Niles says something like "Why do you feel like that?" During this line Niles goes from putting sugar in his coffee to having the mug raised instantly.
Continuity mistake: The pickle being eaten by Bulldog after he enters Frasier's apartment and sits down on his couch gets bigger after Bulldog takes a bite out of it.
Miracle on Third or Fourth Street - S1-E12
Continuity mistake: When Roz and Frasier are exchanging gifts, Roz takes her present out of its box and the box is still at least half covered in wrapping paper. In the next shot, no wrapping paper is visible around the box.
Miracle on Third or Fourth Street - S1-E12
Continuity mistake: When Roz and Frasier are exchanging gifts, when Frasier first puts the lid back on the gift box there is no tissue paper sticking out. In the next shot, a large sheet of red tissue paper is outside the box.
Miracle on Third or Fourth Street - S1-E12
Continuity mistake: When Bulldog is trying to persuade Frasier to cover his shift on Christmas Day, Bulldog's cup of eggnog jumps back and forth from sitting on the desk to in his hand.
Miracle on Third or Fourth Street - S1-E12
Continuity mistake: Early in the show Frasier is wrapping a Xmas present for Roz. The shot cuts to Chopper Dave and then back to Frasier. A bow and gift tag have appeared on the gift, but there wasn't enough time for that to have happened naturally.
Guess Who's Coming to Breakfast - S1-E13
Continuity mistake: Marty, Elaine, and Frasier are sitting down to breakfast. Elaine picks up her mug and in the next shot we see her reach and pick it up again.
Guess Who's Coming to Breakfast - S1-E13
Character mistake: In this episode Roz comments that Noel drives a 1973 Dodge Polaris. There is no Dodge Polaris. There is, however, a Dodge Polara.
You Can't Tell a Crook by His Cover - S1-E15
Continuity mistake: When Frasier and Martin are looking at Frank examining the bowl, the cards on the table change position.
You Can't Tell a Crook by His Cover - S1-E15
Continuity mistake: When Frasier and Niles are in the cafe talking about the Topaz Room, the waiter goes from bending over the table to collect the money to upright a few feet from the table instantly.
You Can't Tell a Crook by His Cover - S1-E15
Continuity mistake: When the doorbell rings Martin leans over to put the cards down, you see him do it twice.
You Can't Tell a Crook by His Cover - S1-E15
Continuity mistake: When Linda opens her beer, her three piles of poker chips are arranged in a triangle. In the next shot, they are laid out in a line, but she has not moved them.
The Show Where Lilith Comes Back - S1-E16
Visible crew/equipment: Halfway through the episode the boom mic is visible at the top left of the screen above Lilith. (00:10:00)
Answer: In the last episode, they explained that Tossed Salad and Scrambled Eggs is a metaphor for the mixed-up people to whom Frasier dispenses his radio psychiatric advice.