Trivia: Part of the line "Shame about the French, really, obsessed with raisins. Humiliated grapes, really," said by Jack in a deleted scene, is similar to a line used in Johnny Depp's other film, Benny & Joon (1993).
Trivia: In the romantic scene between Elizabeth and Will where she shows him the medallion, she pulls it from around her neck. The necklace was attached to the back of her neck with sellotape to make it easily removable, but the first few times she pulled it off the tape was too tightly attached and pulled bits of hair off too. Commentary, DVD.
Trivia: The phrase that Jack and Gibbs utter in the Tortuga pub, "Take what you can. Give nothing back," was actually inspired by the crew of the "Lady Washington," the ship that played the "Interceptor." It refers to taking in a ship's sails during a high wind and not letting any canvas slip back. (DVD commentary).
Trivia: The leather cuff Jack wears in the movie is based on one that Johnny Depp wore in another one of his movies. The costume designer rented all of his movies and watched them in order to duplicate the exact leather cuff Johnny wanted.
Trivia: Young Elizabeth sings a pirate's song in the opening shot. It is the same song that Elizabeth teaches Jack when they are marooned on the island. At the end aboard the Black Pearl, Jack starts to sing that song when he says, "Bring me the horizon." This song is from the PotC ride at Disneyland.
Trivia: The scene where the prisoners in the jail cell are trying to get the dog to give them the keys is taken straight from the ride in Disneyland. The costumes and dog are even the same.
Trivia: On the bonus DVD deleted scenes segment, there an improvised scene where Jack is trying to remember the word 'Parlay' and goes on to talk about the French. He says at one point 'they're great singers'. Johnny Depp's girlfriend at the time was the French singer Vanessa Paradis.
Trivia: Jack Sparrow has lots of braids and beads in his hair. If you look closely, you can see that in the posters and other merchandise, the braids are on the opposite side than they were in the film.
Trivia: In the previews on TV Elizabeth Swann is shown in the water in a purple dress with a shark swimming in front of her, but in the actual movie you don't see this. This probably would've happened after she walks the plank, but she had taken off the dress already and there simply is no shark.
Trivia: On set, Johnny Depp wore gold teeth, which he often forgot to take off after filming.
Trivia: The boat that Johnny Depp arrives in at the pier actually did sink. Fortunately, the crew had already completed their shooting involving the boat, and so they left it there.
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