Continuity mistake: When Chigurh places his handcuffs around the police officer's neck to choke him, the handcuffs are more like manacles and contain 7 or 8 links between the cuffs. When he goes to wash the blood off of his wrists and drops the handcuffs in the sink, they are much smaller, containing only 3 links between the cuffs. (00:03:05 - 00:03:45)
Continuity mistake: In the scene where the two sheriffs inspect the burning car, Wendell puts his thumbs in his back pockets, where they remain for the next two shots from behind. Shots from the front, however, have Wendell's left hand in front, with his thumb through his belt. (00:27:30 - 00:28:30)
Continuity mistake: After Chigurh kills the three Mexicans inside the motel room, the dead body of the second man with the meter in the hand changes position in two detached shots. At first he has his head on the ground, then he keeps it pressed from behind against the cistern toilet. (00:50:28 - 00:51:09)
Continuity mistake: When Moss unloads the shotgun onto the diving Chigurh, Chigurh's right thigh is towards Moss, but later when C fixes his wound, it is his left thigh he's repairing. (01:04:14)
Continuity mistake: When Harrelson visits Brolin in the hospital, the small white flowers to our right are in random conditions of wilting throughout the scene, starting quite down, then way up and everywhere in-between. (01:14:50)
Continuity mistake: Chigurh is cut deeply on his wrists when choking the officer with his handcuffs at the beginning of the movie, but later when he is doctoring the wounds on his leg, his wrists are completely visible and there are no recent injuries.
Continuity mistake: In the gas station scene, Chigurh places a crumpled candy wrapper on the counter as he is intimidating the owner, and the camera stays on the wrapper for a few seconds as it unwrinkles itself. Moments later, as Chigurh reveals the coin toss result, it is a completely different, blue and white wrapper.
Continuity mistake: When Llewelyn is talking to the woman beside the pool at the Sands Motel, his gun satchel is by his side. During the cutaway shots back and forth between Llewelyn and the woman, the distance between the gun satchel and Moss changes several times.
Continuity mistake: When Sheriff Ed Tom Bell returns to the motel room where Llewellyn had been shot, his cruiser lights illuminate the room after he opens the door. We see the horizontal shadows cast by the police crime scene tape on the walls of the room, including the back wall,above the picture, as Bell walks through the room. After returning from searching the bathroom, however, there is no longer a tape shadow on the back wall, as he sits down on the bed. Note, that in the next camera angle shot of him turning his head to look down at the open vent, you can again see the shadows on the side wall, indicating the tape should still be intact and headlights still on.
Continuity mistake: In the motel room scene at The Del Rio Regal Motel, after Chigurh kills the Mexicans in his stocking feet, he removes his socks and tosses them into the bathroom. In the following shots, as he begins searching the room, we can see his bare feet. After he notices the vent above the doorway, however, the camera focuses downward on his hands, as he reaches into his pocket for change to use to unscrew the vent cover. The camera in that shot is in close-up focus on the hands, but, looking down toward the floor, you can make out the familiar reddish-brown, pointed toe boot on his right foot.
Continuity mistake: When Chigurh enters the hotel room and encounters the Mexicans, he shoots the guy on the bed. He then shoots the wall next to the TV. The bullet holes on the wall are behind the TV. The TV does not receive any damage from the gun blast. The angle is such that it looks like the TV should have been damaged by the bullets.
Continuity mistake: After Chigurh escapes from the police department in the police cruiser, he pulls over the white 1977 Ford in order to "swap." As both cars pull to the shoulder of the road and stop, a long shadow is being cast onto the highway by the Ford. In the next shot, as Chigurh is walking up to the Ford, the shadow does not even reach the pavement, indicating that the second shot was filmed much closer to mid-day.
Continuity mistake: When Llewellyn places the money satchel into the motel (room #138) air vent there are a number of dust scratches to the bottom left of the vent. Then later on when Chigurh opens the vent with his dime and you look at the character shot from the inside the vent (from room #38), the scratches to the left are not there.
Continuity mistake: During the dialogue between Moss and Wells at the hospital, there is an ashtray on the bedside table next to him changing position in various shots.
Continuity mistake: Near the end of the movie in the car accident scene, when Anton steps out of the car completely injured, the door's window appears broken in a way and then in a different one in a next scene.
Continuity mistake: During the gas station scene, Chigurh is continually eating from his bag of nuts. During the conversation between Chigurh and the attendant, as the camera cuts back and forth between them, Chigurh keeps eating a nut from behind, and then from the front, his hands are by his side and he eats a nut again. This occurs several times throughout the scene.
Answer: That's intentionally left ambiguous - it's open to your own interpretation.
Twotall