Continuity mistake: When Gaston and Lefou are talking to the man in the bar, Gaston throws the bag of gold to the lantern's right. However, when this man says, "So you want me to throw her father into the asylum?", the bag is now on the lantern's left.
Continuity mistake: When Lumiere and Belle go into the dining room before the 'Be our Guest' song, in a wide shot when Lumiere says "Ma chere mademoiselle," you can see by the left wall there is a stone statue of a bird. However when it cuts to the following closeup of him, the statue has gone. (00:36:40)
Continuity mistake: In the "Be Our Guest" number, Mrs. Potts notices a large spot of dirt on her side. Then when the napkins wipe her, you can see the one large spot of dirt had turned into three small spots of dirt. (00:39:05)
Continuity mistake: When Gaston comes to Belle's house to propose to her, you can notice that he leaves the door open, but when he backs Belle against it, the door has magically shut. It is definitely the same door - note the items surrounding the door, and the door itself are all the same. (00:17:05 - 00:17:50)
Continuity mistake: When Gastons mob start to bang the front doors with the tree trunk, in one shot of them banging, the door handles are gone. Then two shots later they've returned. (01:10:55)
Continuity mistake: When Belle is coming to the West Wing there is a big statue of a monster with its mouth open very near the door. When Belle is shown running out of the West Wing later, this statue has disappeared.
Continuity mistake: After Belle lets Mrs. Potts in and walks backwards into the wardrobe, the panelled wall is bare. Then in a later wide shot when the wardrobe says "We all think so." there is a wall candelabra in between two panels which then disappears again later, when the wardrobe opens her doors and the moths flutter out. (00:30:20 - 00:31:10)
Continuity mistake: At the end of the film the Beast smashes through the glass window and a lot of it lands on the balcony. When Belle is with the wounded Beast, the glass has vanished.
Continuity mistake: When Belle is in her bedroom at the castle for the first time, Mrs Potts and Chip come in to give Belle a cup of tea. There is tea in Chip when Belle drinks but as the camera closes in on Chip there is no tea. Then as Chip bounces out of the door tea comes spilling out.
Continuity mistake: After the scene where Chip bursts into the cellar, there is a wide shot of outside of the castle as the villagers get beaten up in which the windows next to the doors are gigantic. In other scenes, the windows are nowhere near that big.
Continuity mistake: When Lumiere and Cogsworth are following Belle, they open a door and run into a tower. The shape of the bolt at the bottom of the door changes between shots.
Continuity mistake: For most of the scene where Maurice is sitting by the fire, the chair he is on is over the checkered part of the carpet. However, when the Beast enters the room and growls "Who are you? What are you doing here?" two of the legs are over the red part of the carpet.
Continuity mistake: The settings and conditions of the West Wing change drastically. For instance, in the beginning, the painting is very close to the rose and there's also a red carpet underneath it, but later the painting is further from the rose and the red carpet disappears. When Belle leaves the room after the Beast releases her, there are red decorations on the floor in front of the door which were not there earlier when the Beast burst in after Belle refused to go to dinner with him. There is usually a lot of junk cluttered in the West Wing, but when the Beast takes a bath it looks much cleaner. It's an almost endless list.
Continuity mistake: When Belle sees Maurice's machine for the first time, the axe on the machine changes between shots.
Continuity mistake: When Gaston spits out the bit of belt during the 'Gaston' song, there is a frog decoration visible. It wasn't there in the opening shot of the tavern though. (00:25:10 - 00:27:20)
Continuity mistake: When Maurice enters the castle doors for the first time, he walks forward, calling "Hello ... Hello?", and there are clearly TWO pillars at the side of the door. Then, in the overhead shot, when he calls "I don't mean to intrude...", there is only ONE pillar!! (00:13:15)
Continuity mistake: When Gaston and Le Fou talk to the Asylum Keeper, in a wideshot Gaston finishes his beer and puts the beermug down. Then in the shot when Gaston says "I've got my heart set on marrying Belle", the mug has vanished. It then returns in the following shot. (00:48:00)
Continuity mistake: When Maurice enters the castle for the first time, there are windows on either side of the front doors. These were not there when Maurice had looked up at the castle after arriving.
Continuity mistake: The length of the chip on the axe in Maurice's invention changes in the scene where he is building it, and also later when Chip is trying to get it to work.
Continuity mistake: During "Gaston", Gaston shoots his blunderbuss three times. However, four holes appear in the ale barrel.
Answer: The Rose started wilting at The Beast's 21st birthday and could have presumably started wilting years before the first time we saw a petal fall off. Given the fact that Lumiere stated that they were living with the curse for 10 years, prince Adam could be 23-24 years old at the time of the original movie,13-14 at the time of the curse, and the Rose could have been wilting for two to three years. This is my best guess given the approximate age of Prince Adam in the ripped up portrait before he was the Beast.