Continuity mistake: Barbossa rips the chain and medallion off Elizabeth's neck, puts it into her palm, then cuts her hand. He takes her hand in his and he turns hers over so it's palm down. The chain can be seen in the close-up and wide shot, dangling down between her fingers and the chain is NOT clasped shut. In the next close-up of the chain and medallion falling into the chest, the chain IS clasped shut. (01:11:55)
Continuity mistake: When Will and Jack are in the bar in Tortuga, Will stands with his back to the wall and on that wall is a shelf with a candle. The candle height changes and the candle drippings are very different in these shots too. Also, shots in the deleted scenes. (00:52:10)
Continuity mistake: When the medallion drops into the chest, and when Barbossa removes it, there is blood on both sides of the medallion. When Barbossa hits Elizabeth and she falls, the medallion falls near her. In this shot we do not see any blood on the medallion. Yet when Will rescues Elizabeth, she reaches for the medallion and it now has a very obvious blood stain on it. (01:12:20 - 01:13:35)
Continuity mistake: Jack and Will duel on the cart and in a side shot, the FIRST time Will crosses his two swords in front of him below his waist, the blade in his left hand is on top of the blade in his right hand, then in the following front shot, the blade in his right hand is now on top of the blade in his left hand. (00:25:15)
Continuity mistake: There are two shots of an unconscious Mr. Brown and the area around him, when Jack and Will approach him. Just before and after Jack grabs the red hot sword out of Will's hand and tosses it, Mr. Brown is seen behind Jack. In these shots Mr. Brown's placement is different in comparison to the tools above him on the ledge. Also in this shot, the tools on the floor to his right in the earlier shots, are not in the same place either. When Will says, "I practice three hours a day so when I meet a pirate, I can kill it," the actual tools to Mr. Brown's left are different. (00:21:05 - 00:24:20)
Continuity mistake: At the dock in Port Royal, in the close-up as Jack makes his escape from the Marines, he is standing on the beam as he throws his shackle chain over the rope. The ledge to his left, just under the rope, has a metal support that is flush with the wood's edge. In the next wide shot as Jack starts his descent down the rope, the ledge and its metal support are not the same as in the close-up, they are obviously very different. (00:20:10)
Continuity mistake: After her anchor is lowered, there's a front shot of Interceptor as it splashes wildly and a crewman that is dressed as Will is seen up on the port side of the rigging. After Elizabeth shouts, "Let go!" the crewman dressed as Will is up on the rigging, but now he's on the starboard side of the rigging. This is not a flipped shot, the sails are different in both shots too. (01:24:25)
Continuity mistake: Aboard the Interceptor, after Elizabeth lifts the hatch and comes up on deck, Anamaria says, "The Black Pearl. She's gaining on us." In the very next shot of Elizabeth, behind her on deck is the crewman with the tan hat. In the next shot as she looks out towards the Pearl, up at the top of the rigging are two crewmen, one of them is the same crewman that was just on deck in the previous shot. He's the one who stands on Cotton's left in Tortuga when Jack inspects the "able-bodied crew." (01:21:25)
Continuity mistake: At Jack's hanging, as the official says, "Impersonating an officer in the Spanish Royal Navy," in this far shot, we see the scaffolding and the Marines walking on wall behind. In the next shot, he says, "Impersonating a cleric of the church of England," and we still see the Marines. Then in the next shot, a close-up of Jack, we also see the Marines. These are successive shots, yet the Marines are NOT in positions of continuous walking. (02:05:05)
Continuity mistake: After falling off the parapet, Elizabeth is under water, and we see a close-up of the medallion floating freely, causing a tremor in the water. When Jack gets her back on shore and rips open her corset, the medallion is now firmly tucked inside her dress - no way it could have just slipped in there given how insanely tight it was. (00:15:40)
Continuity mistake: Barbossa says, "Buried on an island of the dead what cannot be found, except for those who know where it is." In this shot only the objects in the center of the table slide down towards Elizabeth, including the two candelabras and her plate of food, having nothing to do with the object's weight. The objects that face Elizabeth on the table to her left and to her right don't move, only those on the moving center track. Also seen on DVD 2. (00:56:45)
Continuity mistake: Aboard Interceptor, Will points his sword at Jack, and Jack swings the boom that slams into Will. In the side wide shot as the boom comes toward Will, when we see Will's hands as he grasps the boom, he is not holding the sword, nor do we see it drop or see it on the deck; however, we do hear it hit the deck. In the next shot, Jack picks up Will's sword near the line and rail, where it didn't exist in the previous shot. (00:49:35)
Continuity mistake: As Will and Grapple fight, in the shot facing Grapple after Will's sword is hurled away, Grapple grabs Will directly around the back of his neck with the grapnel and starts to pull him close. However, in the next shot facing Will, the grapnel is only at Will's shoulder and left arm, as Grapple pulls him close. (00:34:55)
Continuity mistake: After being rendered unconscious by Will, a dazed Jack Sparrow runs into the pirates in the caves after the first blood sacrifice attempt. He turns around and faces Jacoby and another pirate. He turns around once again to face Pintel and all the others. But of the four shots showing Jack, one shows only Jacoby behind him, two just show the smoke from Jacoby's beard, and one shot in between, shows no pirates standing behind Jack at all. (01:15:20)
Continuity mistake: When Gillette puts the iron shackles on Jack, as Elizabeth offers her protest, in the shots facing them, there is a barrel with a green sack on top of it and two wicker rods against the stone wall. However, when Norrington says, "Indeed," then when Jack says, "Finally," and also when Jack says, "I saved your life. You save mine. We're square," the barrel, sack and rods are not there. (00:18:25)
Continuity mistake: After Jack rescues Elizabeth, he slices the front ties of the corset she is wearing, and gives the corset to Murtogg. As he hands Murtogg the corset in the first shot, the corset is right side up, because we see the waist flaps at the bottom. In the next shot, as Jack's hand lets go of the corset Murtogg is seen holding the corset upside down with the shoulder straps at the bottom. In the next shot, a close-up of Jack, in the background Murtogg is holding the corset right side up, and the waist flap is seen. (00:16:35)
Continuity mistake: When young Elizabeth holds up the medallion, and she sees the Black Pearl, her fingers are positioned differently in the wide shot and in the close-up shot of the medallion. (00:04:40)
Continuity mistake: Aboard Interceptor, Will and Elizabeth are below deck, and seen on the table are candles on a plate. The three candles and the melted wax on the plate to the right of Will's elbow, differ in the opening shot, when Will says, "Here let me," and when he has the medallion and slams it down onto the table. The candles do not melt so quickly, while they have this very short conversation. (01:17:35)
Continuity mistake: Before Jack says, "Ta," there's a close-up of their feet and there's a 2x4 edge on the cart. Later, Jack tosses the mallet at Will, who ducks down, the cart's seen and there are two strips of wood as the edge. When Jack flips a plank, it smacks Will in the face, he falls and that end of cart's seen and now there's no finished edge. When the barrels fall on the edge of the cart, we see the 2x4 edge again. In many shots throughout the scene the edge changes. Also, in a couple of shots the edge has a cut out in the corner, for the wire they used. (The wire can be seen on Disc 2.) (00:23:35 - 00:25:30)
Continuity mistake: As Jack bids farewell, in his extreme close-ups, when he says, "Elizabeth. It would never have worked between us, darling. I'm sorry," the soldiers behind him are lined up differently in these shots than in the wide shot just before and after, when Jack starts to walk away. (02:09:00)
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