Continuity mistake: When Brenda and Nate are arguing (on the verge of breaking up), the top of Brenda's sweater goes from folded over to laying flat a few times during the scene.
Continuity mistake: When Nate drives his motorcycle out to the cliff overlooking the beach, we see him get off his bike wearing his helmet and glasses. He strides along and then before stopping takes off his helmet and not his glasses. In the very next shot he is squatting down and his glasses are gone, but he made no attempt to take them off and there wasn't enough time in between shots to do so.
Continuity mistake: When Keith picks up his sleeping niece, the shot from behind him shows her hand on his shoulder, near the side of his neck. When the shot changes to face him, Taylor's arm is wrapped behind his neck, her hand out of view.
Continuity mistake: After dinner when Ruth and Nikoli are in the kitchen, Nikoli is drinking vodka; the bottle is on the table next to him. In one shot he is holding his glass and the view suddenly cuts to Ruth but we can still see the table and the bottle; his glass is now next to the bottle. There was no time for him to put it there in between the shots.
Continuity mistake: When Brenda and her mother are at the restaurant, Brenda's cup moves from her left to her right hand instantly when the camera angle changes.
Answer: Nate actually say "You can't take a picture of this, it's already gone." It's kinda hard to explain, but he's referring to the fact that the moment Claire wants to take a picture of is over already, and she can't take a photo of it, just a different, lesser moment.