
The One with the Stoned Guy - S1-E15
Continuity mistake: When the stoned guy eats all the shrimp ravioli, he eats everything including the garnish. When we next see the plate, the garnish has returned. (00:17:30)

The One with Mrs. Bing - S1-E11
Continuity mistake: When Joey says to Ross in the hall 'you didn't call and leave your grip size' his arms are folded. In the next shot, his arms are behind his back. (00:10:20)

The One Where Nana Dies Twice - S1-E8
Continuity mistake: When Ross falls into the grave he ends up with a massive mud patch on his knee. He turns over and it's gone. (00:14:30)

The One with the East German Laundry Detergent - S1-E5
Visible crew/equipment: When Rachel jumps into the cart, and the rude woman is bending over, you can see a mike pack underneath the back of her T-shirt. (00:21:30)

The One with the Dozen Lasagnas - S1-E12
Visible crew/equipment: When Ross is on the balcony trying to comfort Rachel after she has split up with Paolo, we see a couple of shots from the balcony looking into Monica's apartment. If you look at the top of the screen you can see where the walls of the set end, and all the stage lights hanging from the ceiling of the studio. (00:18:35)

The One with the Dozen Lasagnas - S1-E12
Continuity mistake: When Ross is on about calling immigration, his hands move with no time to do so. (00:04:05)

The One with Two Parts: Part 1 - S1-E16
Continuity mistake: At the start of the episode, Chandler is holding onto a menu with his right hand. In the next shot, it is gone. (00:00:10)

The One with the Stoned Guy - S1-E15
Continuity mistake: When the stoned guy says they should make macaroni and cheese, Monica holds out her hands. In the next shot, her hands are clasped together. (00:18:50)

The One with the Blackout - S1-E7
Revealing mistake: When Phoebe says something like, "Look, the last candle is about to go out", she starts counting down, saying "-47,-48..." and you can see Monica looking at the candle. But there is a light source behind her (it can't be a candle because she is looking at the last candle). (00:20:05)

The One with Two Parts: Part 1 - S1-E16
Visible crew/equipment: At the end of this episode when Rachel falls off the balcony, when we are looking out from Mr. Heckles' apartment, a boom mic is visible at the top of the screen just above him. (00:21:30)

The One with the Monkey - S1-E10
Continuity mistake: When Rachel says about her 6th date with Paulo, she is holding a decoration for the tree. In the next shot the decoration changes to a much larger object. Then, in the next shot, as she hands it to Monica, it has turned back to the original shape. (00:05:40)

The One with Two Parts: Part 1 - S1-E16
Continuity mistake: Just after Marcel switches the TV to "SAP," Joey comes back and tells Chandler about Ursula and how she gave him extra food. Chandler is holding a bottle of water, and before the camera cuts to Joey it is open, but when he is talking it is capped, and finally when Chandler says "Score," the bottle is open again. (00:07:05)

The One with the East German Laundry Detergent - S1-E5
Continuity mistake: When Joey and Angela talk in Central Perk, the black waitress with long hair is visible the background of shots of Angela. When we see shots of Joey the same waitress is also behind him near Gunther. She is in two places at once. (00:05:50)

The One with George Stephanopoulos - S1-E4
Visible crew/equipment: When Monica climbs out the window with the pitcher of Tiki Death Punch while Rachel and Phoebe are on the balcony, we can see the end of the set wall inside and a crew member moving around back there.

The One with the East German Laundry Detergent - S1-E5
Continuity mistake: When Rachel is holding the ice pack to Ross's head at the end of the episode, Ross' left hand is lowered, then in the next shot, it is raised to his head. (00:21:35)

The One with the East German Laundry Detergent - S1-E5
Continuity mistake: When Rachel says 'everything looks like jammies now' she is holding up a t shirt. In the next shot as she throws it down, it is now folded up. (00:17:00)

The One with the Thumb - S1-E3
Continuity mistake: When Lizzie holds the tin foil hat up to Phoebe, in one shot she holds it out with one hand, then in the next shot she is holding it in both hands. (00:12:10)

The One with the Sonogram at the End - S1-E2
Continuity mistake: When Rachel asks Phoebe if she is a twin, she is wiping the table next to her. In the next shot Rachel has her hands together. (00:11:40)

The One with the Dozen Lasagnas - S1-E12
Continuity mistake: During the scene where Phoebe is telling Rachel that Paolo made a pass at her, Rachel unrolls a long length of kitchen roll. During the scene there is a shot over her shoulder where we see that the kitchen roll is as normal and in the next shot we see it unrolled again. (00:15:30)

The One with the Sonogram at the End - S1-E2
Continuity mistake: At the start of the episode when Chandler is talking about Pink Floyd, his legs are both on the table. When the shot changes, his right leg is resting on his left knee. (00:00:50)
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