Continuity mistake: When Ryan and Lindsay are making out, Ryan's hands change position in different camera angles, as well as the way Lindsay is sitting when Kirsten interrupts them.
Visible crew/equipment: At the beginning of the episode, where there is a shot of the poolhouse, look at the top right hand corner. You can see where the set ends.
Continuity mistake: When Seth is eating alone in the restaurant, there is a plate with leftovers in front of him. In the next shot, when Zach arrives, the plate has moved to the top right side of the table.
Continuity mistake: In the scene where Summer first goes in Marissa's room, Marissa's hairstyle changes - her hair is in a ponytail for most of the scene but in close-ups she has a visible fringe. (00:07:25)
The Shower - S1-E25
Continuity mistake: Aunt Cindy's arms change position back and forth, between holding her drink with two hands, and holding with one hand and the other on her hip, while talking to Caleb and Julie at The Shower, when Julie is trying to get Cindy to leave them alone.
Character mistake: Caleb tells Julie that when he had his coronary, she was in a spa in Nice, even though in the episode before it was established that Julie cancelled her trip to Nice.
Continuity mistake: When Sandy meets Rebbecca in the coffee shop to discuss her running away, Rebecca's coffee cup alternates from being down on the table to by her mouth, when you see her from behind, between shots.
The Chrismukkah That Almost Wasn't - S2-E6
Continuity mistake: When Seth is holding the wheel of jobs for Chrismukkah the arrow on the wheel changes positions repeatedly in between shots.
Continuity mistake: At the start of the episode when Sandy and Kirsten are talking at the kitchen counter, Sandy is drinking juice. After the camera switches to Kirsten and back to Sandy, his glass is fuller than it was before.
The Case of the Franks - S4-E13
Revealing mistake: When the limo pulls up to the hot dog stand, Julie steps out from the back seat. And as she walks toward Frank standing in front of the picnic tables, the limo driver is visible behind the wheel. Julie joins Frank at a table, and then Ryan decides to enjoy a last spin in the limo telling Taylor they've rented it for 2 more hours. In the next shot they are sitting in the front seat talking while Ryan is at the wheel, when the limo driver never left the vehicle. (00:41:20 - 00:42:46)
Answer: He means that if Alex has to go so far as to forbid Ryan from seeing Marissa in order to maintain her relationship with her, their relationship obviously isn't working.