Visible crew/equipment: As Norrington says in the wide shot, "Jack Sparrow, isn't it?" to which Jack replies, "Captain Jack Sparrow, if you please sir," there is a black-haired crew member wearing a white shirt who is crouched down behind Jack. Really! He's also visible when Mullroy says, "These are his sir." (Visible ONLY on the video version.)
Continuity mistake: When Elizabeth walks the Black Pearl's gangplank, we see that it is long and out of swords' reach. When it is Jack's turn to jump, the crew is up on him (with swords) because Jack is at the start of the plank. Barbossa then throws the gun into the water. Then, when Jack takes off after it, his dive is taken from the end of the plank without having moved there.
Visible crew/equipment: As Will and Jack duel up top in Brown's shop, in two close-up shots a large plank is visible at their feet with two long black marks along each side detailing where the beams are supposed to be, so that Orlando Bloom and Johnny Depp know where to land as they supposedly leap from beam to beam and feign keeping their balance. (This is ONLY visible on the video version.)
Visible crew/equipment: On the dock, when Jack grabs the rope, flies up and escapes, the cannon comes crashing down onto the dock. When the wood planks break (pre-cut wood), two Marines fall into the hole. Seen hanging under two of the remaining fixed wood planks are strips of tape that was used to help secure the pre-cut wood together with the fixed wood. Another view of this is also seen on DVD 2. (00:19:45)
Visible crew/equipment: Will grabs the red hot sword and during the 'white light', Will's sleeve becomes translucent so the cable attached to the hilt is seen inside Will's right sleeve. When Will thrusts his sword at Jack's legs, the cable's seen again and the bulge under the vest is from the battery pack. In the close-up, their arms in the air, Will's left hand is about to grab Jack's wrist and the cable is seen openly at Will's wrist, going from the hilt into his right sleeve. The cable's hidden in Orlando Bloom's shirt and is powered by the battery pack (mentioned in another mistake), to supply the power for the spark effect of the sword. (On disc 2, Marc and Tony, rehearse this particular sword sequence and the two cables leading from the hilt are seen dragging on the floor as they duel. On the video, the cables are visible on Johnny and Orlando.) (00:24:15)
Revealing mistake: When the cannonball slams into the pirate at the Swann home, a wire visibly pulls on the back of his clothes and quickly propels him through the back doors. (Clearer in slow motion.) (00:33:15)
Factual error: Captain Norrington is "promoted" to Commodore. However, commodore was not a rank in the British navy (it is now, not then), but a posting. A post captain could be appointed commodore (meaning he commanded more than one vessel) for a specific task, but when that task was completed, he became a post captain again. A promotion would have made Norrington an admiral. (00:11:30)
Revealing mistake: Aboard the Pearl, just as Barbossa screams, "And the rest of you, bring me that medallion," seen to the upper right of the screen is a very apparant high cliffside. There are no cliffs, high or otherwise, where they are having the battle - they're in open water. (01:27:30)
Factual error: When Will delivers the new sword to Governor Swann, look behind Governor Swann. There is an oval painting hanging on the wall. It is a Thomas Kinkade portrait, which would never grace the walls of the mansion. Thomas Kinkade is a modern artist. (00:07:20)
Visible crew/equipment: When Jack and Will duel, Jack says, "You need to find yourself a girl, mate," and he takes a mallet from above, Will ducks. In the next back shot of Will as he ducks, the back, left flap of his vest goes up. There is a battery power pack secured with black tape to the left side at the back of Orlando Bloom's pants' waistband. There are several shots during this scene when a small bulge under the back of his vest can be seen. (00:24:45)
Continuity mistake: At the beginning, when young Elizabeth is holding the medallion and spots the Black Pearl, we can see part of the medallion's back. It's an Aztec design, not a skull. At Elizabeth's blood ritual, when the medallion is dropped into the chest and spins over itself, both sides of the medallion are the same Aztec skull. (00:04:40 - 01:12:20)
Visible crew/equipment: During the cannon attack on the harbour near the beginning of the film, a spring board, used to propel one of the stuntmen dressed as a sailor into the air, is visible during an explosion near the dock. (00:30:20)
Continuity mistake: As Will holds the sword above his head to block Grapple's grapnel, the cloth (the same one he wears around his neck when his sleeve is pulled down) that is tied around his right wrist is visible. He is soon rendered unconscious by a pirate's candlestick. When he wakes he puts his right hand to his aching head and the cloth's knot is visible. The cloth is wrapped completely differently in the two shots, though he never had the chance to change it. (00:34:50)
Revealing mistake: When Barbossa cuts Elizabeth's hand her nails are short. When Will rescues an unconscious Elizabeth at the cave, she reaches for the medallion and her nails are longer. When Will ties the cloth around Elizabeth's hand and she gives him the medallion, her nails are short. However, when Jack says, "Ahh, where's dear William?" her nails are now manicured and much longer. Once she's marooned on the island her nails are short again. Most scenes were filmed out of sequence, hence the difference in nail length. Her nails should have been kept the same short length for the duration of filming. (01:18:35 - 01:29:10)
Revealing mistake: When Elizabeth first sees the skeletal pirates she stumbles backward, and when she lands on the tarp in the close-up, the flesh-covered thumb and part of a hand is visible behind her, at the top right, though the pirates are in skeletal form. (00:59:05)
Continuity mistake: Just after Jack pulls the red hot blade out of Will's hand, Will does a somersault and in the close-up he grabs hold of another sword and swiftly points it up. In the following wide shot Will is just grabbing the sword again. (00:24:25)
Visible crew/equipment: At the blacksmith shop, after Will grabs the sword out of the fireplace just as he and Jack begin to duel around the post, in the wide shot, black straps with attached wire cables are clearly visible around both Johnny Depp and Orlando Bloom's right ankles. (This is only visible on the video version).
Continuity mistake: When Jack first confronts Will at the blacksmith shop, seen behind Jack, hanging on the stone wall near the fireplace are iron masks and other paraphernalia. Later, when Jack sprays the soot at Will, the iron masks and paraphernalia are arranged differently on the wall. (00:23:00 - 00:26:15)
Continuity mistake: While standing near the Aztec chest, Will says, "He didn't waste it," and in this shot there are two buttons closed on his vest, over the belt buckle. Yet, in the close-up of Will's hand dropping the two pieces of gold, there is only one button closed on his vest, over the buckle. (02:01:10)
Revealing mistake: Aboard Interceptor, Jack calls out, "Monkey!" as the monkey jumps onto the broken mast leading to the Pearl and Jack runs after him. In the very next shot of Elizabeth, who's trying to move the broken rigging from the hatch that Will is trapped under, the coloring is off in this one shot. The color of her dress, for example, is not vibrant, it is brown. This is visible on the region 1 DVD and on videotape. (01:29:25)
Answer: The curse needs the blood of everybody who took a coin from the chest. All the other pirates have already contributed so, as the movie opens, the only blood needed is Will's, substituting for his father. During the finale of the movie, Jack takes a coin from the chest, adding himself to the curse, so his blood is now required as well as Will's.
Tailkinker ★
But I didn't see any blood on the coins, and none of the pirates cut themselves, even before Will became part of the mix.
Yes, the other pirates did cut themselves before Will came into it, off-screen. The lack of blood on the coins can simply be explained as most of it dripping to the bottom of the chest, it being washed away by storms blown into the cave, or by the fact that they didn't drop that much blood on it in the first place.
When they had Elizabeth they believed she was Bill Turner's daughter, but they all thought the curse had failed, none of them had cut themselves so it makes zero sense.
They had been collecting back the coins for years. During that time they repaid their own blood. All they needed was the last coin and the blood of Bill Turner to break the spell.
lionhead