The One with George Stephanopoulos - S1-E4
Continuity mistake: Monica asks Phoebe if she has a plan to which she replies she doesn't even have a "Pla." During this, her hairs position on the futon changes between shots. (00:14:40)
The One with George Stephanopoulos - S1-E4
Continuity mistake: The facial expression of the receptionist changes drastically between instant cuts when she says the line "any minute now" (00:14:00)
The One with George Stephanopoulos - S1-E4
Continuity mistake: The way the receptionist in the hospital holds the candy bar differs between the several camera angles. (00:13:30)
The One with George Stephanopoulos - S1-E4
Continuity mistake: When Ross gets hit with the puck, we see it flying towards him. Camera cuts and the puck has simply vanished and yet Ross acts as though he has been hit. (00:12:45)
The One Where Monica Gets a Roommate - S1-E1
Continuity mistake: Near the end when Phoebe says to Monica, "C'mon give me your feet" she puts the red pen down on the blue paper. When Monica sits down though, the red pen is on the table and not the blue paper. (00:23:40)
The One Where Monica Gets a Roommate - S1-E1
Continuity mistake: When Joey makes the joke about Ross being 8, Ross has his right left hand lowered. Camera changes to a different angle and it's raised, before switching back to the 1st angle and being lowered again. (00:15:50)
The One Where Monica Gets a Roommate - S1-E1
Continuity mistake: The way Ross holds the can of beer changes between the full on shots and the shot of Chandler and Joey when just the can is visible on the side of the screen. (00:12:40)
The One Where Monica Gets a Roommate - S1-E1
Continuity mistake: When Joey hides the bracket in the plant pot, the instruction sheet that is on the bookcase disappears instantly. (00:12:20)
The One With the Baby on the Bus - S2-E6
Continuity mistake: When Chandler and Joey fetch Ben from the Department of Health Services, as they say they're both the baby's father, Chandler puts his arm around Joey and Joey takes his hand. When the angle changes you can see Joey's shoulder and Chandler's hand isn't on there. When it cuts back to the front view, his arm is around Joey again. (00:15:10)
The One With Barry & Mindy's Wedding - S2-E24
Continuity mistake: Phoebe takes out her gum before kissing Joey. After she kisses him, she makes a comment about it and her mouth is empty. In the next shot, she sits down and is chewing. But she doesn't put the gum back in. (00:02:22)
The One With Phoebe's Rats - S9-E12
Continuity mistake: When Gavin and Rachel are in Rachel's office, in some shots Gavin is wearing a wedding ring. (00:03:43)
Continuity mistake: When Phoebe goes to visit her mom for the first time, she takes a cookie from the cookie jar and leaves the lid off. But in one shot, the lid is back on. The lid is back off in the following shots. (00:06:36)
The One In Barbados, part 2 - S9-E24
Continuity mistake: As Mike and Monica are playing ping-ping, two people playing checkers magically materialize behind Monica. One second they're not there and the next second they are. (00:12:25)
The One Where Everybody Finds Out - S5-E14
Continuity mistake: When Monica and Chandler come in to ask Joey about Pheobe knowing about their relationship he throws the Hugsy teddy behind him. In the next shot we see behind the chair and Hugsy is not there.
The One With The Giant Poking Device - S3-E8
Continuity mistake: When Ben says Monica's name she's holding the Minute Maid juice box, but in Ben's closeup the juice box is on the table, though it's back in Monica's hand in the next shot. (00:08:50)
The One Where Monica Sings - S9-E13
Continuity mistake: When Phoebe, Monica and Rachel are talking in the coffee house, a waitress walks by and in the next shot when the camera focuses on Monica, and comes back to Rachel, the waitress walks by again. (00:05:00)
The One with the Monkey - S1-E10
Continuity mistake: When David kisses Phoebe in the lab the first time, he writes "yes" on the board. Later on when they are in the lab again the "yes" is different than the previous one.
The One With Ross and Monica's Cousin - S7-E19
Continuity mistake: When Monica comes into Phoebe's apartment for her Surprise Bridal Shower, the view of the hallway outside the apartment is a dead end on the right side (the left side cannot be seen), however, in S7:E12 (The One Where They're Up All Night), both when Phoebe is disposing of the fire alarm and when the fireman is at the door, it is clear that there is another apartment opposite hers, as well as a trash chute on the right side. (00:18:25)
The One With The Stripper - S8-E8
Continuity mistake: In this scene in Central Perk, Monica tells Chandler she has hired a stripper for him as she feels bad for not letting him have a bachelor party, and tells him to think of it as a 2 month anniversary present. However this episode is set 2 episodes after the Halloween episode, therefore allowing us to assume it is set sometime in November or later. Chandler and Monica got married in May, as stated several times in the show by the cast, therefore they have been married for around 6 months or more, not 2 months. (00:07:00)
The One Where Chandler Can't Remember Which Sister - S3-E11
Continuity mistake: When Rachel gets off the phone with Mark she sets the phone on the counter. In the next shot the phone is in the holder and it keeps going in and out.
Answer: The statements that she's contradicting (that it is common, it happens to every guy, and it's not a big deal), are the things that a woman commonly says to a man who is suffering from erectile difficulty, typically to assuage his bruised ego. However, most men do not believe that these statements are true, as evidenced by Chandler's outburst. He's so caught up in the proof that women are lying about it that he gives himself away.
Rooster of Doom