Continuity mistake: When Sarah initially takes a bite out of the peach, the bite is completely different when she is lying on the trash heap and then in the following close-up when she sees the worm. (01:04:25 - 01:09:55)
Continuity mistake: The length of Sarah's nails change considerably between certain shots in this film. For example, after biting the peach she puts her hand on the tree and her nails are short. Upon returning to her home she runs up to Toby, strokes his face and her nails are long. Then, in her room, when she holds the clipping, puts it and the music box, etc. in her vanity drawer, her nails are short again. (01:04:35 - 01:33:50)
Continuity mistake: When Sarah runs to the side of the 'bubble' and smashes the glass with a chair, you can see that the table and the chair that she uses aren't reflected in the glass as she runs up to it. (01:06:30)
Continuity mistake: When Sarah wakes up in the junkyard, there is a wide shot, then a closeup of Sarah holding the peach. Between the two shots, the way Sarah holds the peach changes. (01:07:10)
Continuity mistake: When Sarah wakes up in the junkyard, she the converses with Agnes the Junk Lady, and then Agnes gives her Lancelot. During this scene between different shots, the junk which is piled behind and around Sarah noticeably changes. (01:07:50)
Continuity mistake: When Sarah is in Jareth's 'glass' bubble, as she lifts the chair in order to break the glass, the blue cushion has a perfectly straight seam, the cushion ties are tied to the back of the chair, and the wood underside of the chair is visible surrounded by the tubular frame. However, in the next shot as the chair goes through the glass, the blue cushion seam at the back is very crooked, the cushion tie is gone and the underside of the chair is completely different. (01:09:10)
Revealing mistake: When Sarah takes the chair to break Jareth's glass bubble, the flower adorned lace topped table is seen. Then as she breaks the glass the table is visible once again, however, the way the tablecloth lies and the flowers, cups, etc., are all positioned differently. (01:09:10)
Visible crew/equipment: After the Masquerade dream scene, you see Sarah falling on top of a dump. When she falls, you can see the wires attached to her letting her down. (01:09:30)
Continuity mistake: When Sarah sits down at her vanity table in her fake room, in a wide shot you can see her Labyrinth book laying on the table. The angle the book is laying at changes when Sarah picks it up in a closeup. (01:09:55)
Continuity mistake: Sarah awakens on the trash heap in the close-up and after she looks at the peach she is seen again on the pile of trash. Before the Junk Lady moves, the things around her are quite different in both shots. (01:10:00)
Continuity mistake: When Sarah enters the replica of her bedroom in the junkyard, she has no lipstick on. As she is sitting at the vanity table, a fresh coat of red lipstick has been applied to her lips between shots. She does hold a tube in her hand, yet she never applies any. Then as the replica bedroom begins to collapse, it is apparent that there is now no lipstick on her lips. (01:10:00)
Continuity mistake: When the old hag hands Sarah her lipstick, the actual lipstick is sticking out of the tube. We see that it still is in the mirror shot too, but when it cuts back to Sarah the lipstick is no longer sticking out the end of the tube. (01:10:00)
Continuity mistake: When Sarah is sitting at her vanity table, in one shot she is holding her lipstick by her face. Then in the next shot she picks up her Labyrinth book. You can see the lipstick standing upright on her vanity table, but between those two shots Sarah didn't have enough time to put the lipstick down. (01:10:10)
Other mistake: When Sarah is in the room with the old hag who lives at the rubbish dump, the old hag asks, "What's the matter, dearie? Don't you like your toys?" Connelly is mouthing the hag's lines, presumably as a prompt to recall her own lines. (01:10:45)
Continuity mistake: In the junkyard, after Ludo pulls Sarah out of the garbage room, Sir Didymus says "M'lady look, we're almost there...." and then there is a shot of the gates to the Goblin City. The junk which sits around the gates to the Goblin City is piled rather low. However when Sarah, Ludo and Sir Didymus arrive at the gates, the junk to the right hand side of the gates is now piled up much, much higher. (01:11:30)
Continuity mistake: When the gang encounter the large robot, as the robot forms together, you can see there is a big axe leaning up against the wall, to the right of the robot. The robot then bellows "Who goes," for the first time. Then it cuts to Sir Didymus barking and then in cuts back to the robot taking two steps forward - in this shot, the giant axe which was propped up against the wall, has gone. It then returns in the following shot. (01:12:50)
Continuity mistake: When Sarah and friends are confronted by the massive metal robot, smoke drifts out from behind it. Then in the next shot, the smoke has totally disappeared, and more smoke then starts to drift out once again. (01:12:50)
Continuity mistake: Sarah sits in her fake room, picks up the book, 'The Labyrinth' and is seen in her reflection. She then says, "Through dangers...take back the child you have stolen." When the Junk Lady asks, "Don't you like your toys?" and also when she gives Sarah the music box, Sarah is seen. In each shot the things behind Sarah's shoulders and in front of her are different, yet, the Junk Lady did not add anything between these shots. (01:13:10)
Revealing mistake: Numerous times you can see the 'metal' robot's metal armour and the spikes on the armour wobble like rubber. This is because the whole robot's armour is made of polyurethane foam. (01:13:30 - 01:15:00)
Continuity mistake: This can only been seen in the letterbox version of Labyrinth. After Sarah says, "It's all junk," the garbage lady grabs a ballerina music box and says, "Well what about this, this is not junk," and hands it to Sarah. She takes it, then for a second it cuts back to the garbage lady. The music box is still sitting on the table after it was handed to Sarah. (01:13:45)
Answer: The necklace is a symbol of Jareth's power throughout the story. All the time that Sarah is in the Labyrinth, Jareth has more power than her, because she doesn't really know what she's doing, and isn't taking one particular path, just getting lucky at the right times. At the end, as we all know, Sarah triumphs, and Jareth's necklace changes to admit his defeat.