Continuity mistake: Below deck aboard the Interceptor, Elizabeth gives Will the medallion. When Will clenches the medallion in his fist, the way the chain hangs down his fingers differs in this close-up and in the next shot, also showing his face. (01:19:15)
Visible crew/equipment: After the pirate pries the gold bowl off his head Elizabeth whacks him, then she and Will stave off the other two pirates' swords as together they hold the gold bar overhead. At the start of the next shot as Barbossa and Jack duel, part of the wood plank that Geoffrey Rush and Johnny Depp stand on is visible at the bottom right of the screen. (This is ONLY visible on the video version.)
Continuity mistake: Jack asks, "Where's dear William?" and Elizabeth runs over to the hatch that Will is trapped under. Tied to the hatch is a rope attached between two holes and lying on top is a piece of the broken mast and sail with more rope. In the wide shot of Elizabeth running towards the hatch and the following close-up, the ropes and twisted sail are either lying or tied differently on the hatch in both shots. This has nothing to do with the angle of the shot. (01:29:15)
Deliberate mistake: When Jack Sparrow and Will Turner take a rowboat and put it over their heads upside-down and walk on the bottom of the harbor (about 20 feet deep by the looks of it), wouldn't the rowboat rise to the surface? The amount of air trapped in the boat appears to be around 3-5 cubic meters, even at three that would provide plenty of lift to lift a boat twice that size and both people to the surface. This isn't even taking into account that wood and people are both fairly buoyant in and of themselves, even without the air pocket to aid. This scene is a direct homage to an earlier pirate movie, The Crimson Pirate, in which three characters do the same thing, hence this is a deliberate mistake.
Continuity mistake: In Tortuga, as Will and Jack are seen for the first time, in the foreground is a drunk man teetering on two barrels and another drunk man on the ground drinking what is being poured into his mouth. In this wide shot the man on the ground has his right elbow on a sack on top of a small barrel. In his next close-up, the sack on top of the small barrel is gone and now there is a tied sack between him and the shovel. (00:50:50)
Revealing mistake: In the wide shot, when an unconscious Elizabeth reaches the water's bottom, the body is a mannequin that has been weighted down in the middle. The white mannequin head can be seen as the body meets the bottom. (00:15:55)
Continuity mistake: Elizabeth takes the medallion out of the drawer, and in the first wide shot as she looks at it (*before* she wipes away the dust with her thumb), seen to her left in the corner, are a tapestry chair and small table with a candelabra, between the the french door draperies and the louver trim door. The table and candelabra are partially in front of the door's louver trim. However after Elizabeth takes the dress out of the box, behind Governor Swann (who stands in front of the french door draperies now), to his right we see the same tapestry chair, table and candelabra, but the table and candelabra are further away from the door's louver trim and much closer to the corner now. (00:05:15)
Visible crew/equipment: After stealing Interceptor, on deck Will sharpens his sword as he says, "When I was a lad...my mother raised me...I came out here looking for my father," and Jack responds, "Is that so?" In the next close-up of Will part of the camera equipment is visible at the bottom of the screen. (This is ONLY visible on the video version.)
Visible crew/equipment: As young Elizabeth holds the medallion in her hand in the close-up, the Pearl comes into focus in the distance. In this shot, behind her hand and chain, but in front of the rail and rigging, the top of the white reflector screen is visible as it comes up at the bottom of the screen. (This is ONLY visible on the video version.)
Continuity mistake: Aboard the Pearl, Barbossa says, "Did you not notice? That be the same little island we made you governor of on our last little trip." While he says those words, hair, etc, keeps changing. 1st shot - the wind blows their hair the same way. 2nd shot - Jack's ponytail at the top of his head is blowing in a different direction. 3rd shot - the wind doesn't blow their hair at all. 4th shot - their hair is blowing just like in the second shot. 5th shot - the wind doesn't blow their hair at all again. (01:33:55)
Revealing mistake: Ragetti has a wooden eye, yet, when he rubs it, it makes a funny squeeking sound. When he first comes ashore he has a wooden ball that he obviously palms instead of inserting. Mackenzie Crook, as Ragetti, wears a contact to simulate the wooden eye, and spins it around with his eye. When Pintel takes the fork with the eye out of Ragetti's socket, this ball at the end of the prongs is not made of wood. Props supplied a small rubber ball, and the air hole next to the fork prongs, with the painted 'iris' right above the prongs, can be seen. (00:30:45 - 01:25:30)
Continuity mistake: In the foyer of the Swann home, there is a large floral arrangement on the table. In various shots, the flowers are shown either from the front, left or right side. Regardless of the angle it's seen in, the height and position of some flowers and greenery, more so at the top, differ between these shots. (00:07:05)
Continuity mistake: Aboard the Black Pearl, after Elizabeth walks out onto the deck and sees the skeletal pirates for the first time, in the shots as she stumbles backward and is tossed in mid-air her strapped shoes with heels are visible. After she knocks off Grapple's skeletal head with the wheel, as Elizabeth runs down the stairs her right shoe is perfectly visible and it most certainly isn't one of those pretty shoes with heels. (This is ONLY visible on VHS.)
Continuity mistake: After Norrington orders his men to take young Will below, in the next shot young Elizabeth stands at Dauntless' stern, in front of the mizzen mast and rigging, with the yard arms behind the mast way above her and its full sails. However, in the next close-ups the yard arm and sail are directly behind her, and the sails differ. (00:04:20)
Continuity mistake: After Jack slams the boom into Will aboard Interceptor, then brings him back on deck, Jack points the sword at Will. In Will's close-up, the sharp edge of the blade actually faces Will's neck - the hand guard is at Jack's knuckles. However, in the next shot, a close-up of Jack, as Jack still points the blade at Will, BEFORE Jack flips the sword over, it is apparent that the sharp edge of the blade faces away from Will - the hand guard is at Jack's fingertips. (Though this is visible on the DVD, a better view is on the video.) (00:50:10)
Other mistake: Keira Knightley has very obvious makeup applied to her cheeks and especially her eyes and lips throughout the movie. First example, when she gives Will the medallion in the cabin, and second, when Barbossa points the gun at her, before Jack shoots him. Actresses wear makeup in movies, but the lip color and eye make-up are unrealistic for a kidnapped Elizabeth. It shouldn't be as dark and apparent, as it is in this movie. (01:18:10 - 02:00:55)
Continuity mistake: Jack cuts the ties of Elizabeth's corset and drops the knife down vertically, with the blade pointing up, right beside her head. In the wide shot, just as Norrington runs up, the knife is now horizontal. No one touched the knife. When he removes the corset, in Jack's shot, he hands it to Murtogg to hold and puts his hand down. In the next shot of Murtogg, Jack's hand is still on the corset. (00:16:35)
Continuity mistake: Aboard Interceptor, Will says, "I'm not a simpleton Jack," Jack is near the wheel and tightening the line at the belaying pin on the rail. There's also a line going through a wood cleat on the rail next to the belaying pin. When Jack causes the boom to slam into Will, the rail is seen and the entire belaying pin with its line is missing, as well as the line in the cleat. Belaying pins are permanent and these are not flipped shots. (This is the wood belaying pin that snapped off, hitting Depp in the knee during the mishap, when filming Interceptor's escape.) (00:48:40)
Continuity mistake: During the pirates rampage in Port Royal, Will battles with Grapple. The rope at Grapple's shoulder changes drastically in most of these shots, including going back and forth from hanging neatly, to not being there at all, to different amounts falling. (00:34:55)
Continuity mistake: At Isla de Muerta, during their duel, Barbossa kicks Jack in the face and he falls to the ground. In the first shot, Jack's arm and back land directly beside the spot of moonlight behind him. In the next close-up, his back and arm are at least two feet from that spot of moonlight, though he has not moved. (Difference visible on VHS.)
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