The One with the Dozen Lasagnas - S1-E12
Other mistake: After Carol asks Ross if the lasagna is vegetarian, the camera briefly goes out of focus before Ross says "I'm pretty sure that it is." (00:05:00)
The One with the Dozen Lasagnas - S1-E12
Other mistake: At the end, Monica is playing as red, but we see the blue team score on the foosball table. However, Monica states that she scored and beat Joey and Chandler again. A previous correction says to look closely as the red team scores, That correction is completely invalid as the player in goal is red. Why would Monica score in her own goal? And Also the blue players can be seen to spin. (00:22:10)
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