The Heights - S1-E9
Continuity mistake: Jimmy brags to Marissa that he is having an "actual phone line" installed that day, when in the episode before he is seen using a cordless home phone when Julie rings him after Marissa ran away from the hospital.
Factual error: Marissa tells Ryan that she "has never slept with anyone before" (in the literal sense), which is not true as she and Ryan slept together (in the literal sense) at the motel in Tijuana, and then woke up with their arms around each other.
Continuity mistake: When Sandy, Kirsten and Rachel walk into the living room, Rachel's arms move position between shots.
The Best Chrismukkah Ever - S1-E13
Continuity mistake: When Marissa goes to see the psychiatrist, she sits down and puts her jacket on the arm of the chair. When the shot changes, her jacket is on the other side of her.
Revealing mistake: If you look closely, a bit into the fight you can see that Hailey is not actually putting any trash inside the trash bag. She is just going through the motions.
Continuity mistake: At the end of the game, when the whole group is in the lounge at the Cohens', Luke and Seth are versing each other on the PlayStation. However, the screen shows the game is only in single-player mode, but both Luke and Seth are using controllers.
Revealing mistake: The picture of Marissa and Ryan that Oliver hides is from the pilot episode, at the fashion show hosted by Marissa. However, at the time she and Ryan barely knew each other and wouldn't have an excuse to take a photo together.
Continuity mistake: When Oliver is singing along to "It's Not Unusual" by Tom Jones and is dumping all the pills onto the coffee table, the pills go from being all mixed up to in colour co-ordinated piles, and back and forth.
Continuity mistake: At the start, Summer and Marissa are talking about the weekend. Summer says something like, "I'm going mad over Seth Cohen." The camera swaps from Summer and Marissa. We see Summer first with her hair in front of her ear, then when we cut back after seeing Marissa, Summer's hair has gone to behind her ear.
Continuity mistake: Ryan walks into Oliver's hotel room twice; there are two shots of him moving from behind the hotel room to come in front of it, separated by six seconds. (00:37:30)
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.
Continuity mistake: Ryan and Theresa are walking along the beach with ice creams. The amount of ice cream changes between shots. This is especially noticeable with Theresa's ice cream.
Continuity mistake: Anna's sleeves change while she is playing video games in the student lounge.
Revealing mistake: The phone message that Ryan leaves on Luke's voicemail is different to what he originally said, which is "I want to make sure you took care of it. Take care of it," but the message recorded is, "I'm just calling to make sure you took care of it. Take care of it." Also the background sounds from the club - the music, people talking, etc, are missing.
Other mistake: In this episode when Marissa and Summer meet Cody Briches on the beach, Marissa says she's never watched "The Valley," which is not true, as in the Valentines Day episode, she's lying on the couch watching T.V and you can hear "Next Time On The Valley."
Plot hole: Ryan says that he has left his watch at the motel after sleeping with Theresa, and goes back to get it. However, at the end of The Goodbye Girl (the episode before) he is seen wearing it as he gets out of the car to go and talk to Theresa, only to find she's gone back to Chino. The whole story of Ryan and Seth going back to get his watch from the motel is just an excuse for them to discover the whole Luke/Julie affair.
Continuity mistake: Marissa walks inside, pulls off her dress, and puts on her pink top, doesn't put on any pants but in the next shot she's wearing jeans.
Continuity mistake: The lighter and packet jump into The Nana's hands after she stubs out her last cigarette.
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: When Ryan and Marissa are play-fighting in the Balboa Bakery, their arms change position repeatedly.
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.