Continuity mistake: When Grace is cleaning the table with the playing cards on it, all the cards are separated in piles on the table, but in the next shot they're all in one big messy pile. Grace holds a small piles of cards, and never touches the big messy pile, then in the next shot she picks somehow up all the remaining cards in one neat pile
Continuity mistake: When Karen arrives late to Mason's swim meet, Jack balls her out, and she stirs the Bloody Mary she's holding then throws the celery stalk down into the pool. Yet, two shots later, as Jack rides his scooter out, the long celery stalk is amazingly back in her drink.
Continuity mistake: When Grace tells Will that it is laundry day and that she has been wearing a peach bridesmaids dress all day, Will says, "Oh, um there's a roll of quarters in my top drawer right beside." When he says that he has a fork on his hand, when the shot changes he says, "My eye cream and my pedicure kit," suddenly the fork has disappeared.
Continuity mistake: In the scene in which Will is sitting in Bobbie Adler's bathroom, talking to Jack on the telephone, the shots alternate between the bathroom and Jack's bedroom. At the beginning of their conversation, the digital clock in Jack's bedroom reads 12:07. For the next few shots, each time the audience is taken back to Jack's bedroom, the time on the clock has changed according to the actual time lapsing in the scene. However, in the middle of this sequence, the digital clock suddenly reads 12:24, where it had read 12:09 in the shot immediately preceding. Finally, in the very next shot in Jack's bedroom, the clock has gone back to "real time," with a reading of 12:10. The assumption is that the shot in the middle of this sequence had to be re-done, thus reflecting the time passage on the clock.
Continuity mistake: When Jack reveals to Will that he is too shy to ask out the sales assistant in the Banana Republic, Jack stands by a wooden shelf. Between shots the positions of his hands on the wooden pole keep changing, and which hand is holding it with also differs.
Continuity mistake: When Jack is lying on the table, with the huge bowl on his face, the position of the boxes behind him on the table changes a few times. In one shot they're half hanging off of the table, in the next shot they're fully on the table etc.