Continuity mistake: In 'Gone', when invisible Buffy is typing on the social worker's keyboard the letter 'B' is pressed several times. When she prints what she's been typing seconds later it's revealed to be "All work and no play make Doris a dull girl", a phrase which contains no 'B's. (00:21:10)
Life Serial - S6-E5
Continuity mistake: Warren switches from holding Jonathan's magic bone with one hand to two hands between front and reverse shots. (00:19:10)
Continuity mistake: The wreath on the front door of the Summer's house disappears just after Tara tells Willow she will be doing the spell. It reappears in the next shot from outside the house.
Once More, With Feeling - S6-E7
Continuity mistake: When Buffy is singing her final song in the Bronze Tara and Anya are standing in the background watching, if you look closely you can see their hands keep changing places between shots, crossed to uncrossed and so on. (00:42:00)
After Life - S6-E3
Continuity mistake: When the demon is attacking Buffy in her room right after Willow's spell has made it corporeal, there's a shot from behind of it drawing back its left hand, followed by a shot from the front of it delivering the backhand with its right hand. (00:34:40)
Continuity mistake: In the alleyway scene after the real Buffy kills all the Hellions (biker demons) and runs off, one of the Hellions can be seen getting up behind Xander. We then see a closeup shot of the Hellion opening its eyes while still lying on the ground and then they stand up and sneak up behind Xander again.
All The Way - S6-E6
Continuity mistake: After Spike has fought with the vampire claiming to be a rebel and he is re-loading his cross bow, he is tackled by another vampire and you can hear the sound of the cross bow firing, but as he falls you can see the arrow is still loaded.
Once More, With Feeling - S6-E7
Continuity mistake: During "Something to Sing About, when Buffy sings, "You don't get to rehearse," Tara walks past the support pole behind her. In the next shot from an angle, she's closer to the middle of the room and the pole is not visible. (00:41:40)
Once More, With Feeling - S6-E7
Continuity mistake: When Buffy is singing "Something to Sing About", she sings the verse beginning 'All the joy life sends, family and friends', and we see that Anya and Tara are stood in the background, about 3 metres apart from each other. However, for one shot, they appear less than 1 metre from each other. (00:42:05)
Once More, With Feeling - S6-E7
Continuity mistake: The demons that Buffy fights in 'Once More, With Feeling' change positions on the floor during the next song. (00:43:45)
Once More, With Feeling - S6-E7
Continuity mistake: In the musical episode, 'Once More, With Feeling', when Buffy is singing her song in the Bronze, 'Something to Sing About', she breaks a pool cue over a demon's head. She holds the remains in her right hand and clubs another demon in the face with it, then the camera cuts to another angle and it's in her left hand when she stabs the next demon with it.
Continuity mistake: New boss Lorraine unfolds her arms twice. (00:39:05)
After Life - S6-E3
Continuity mistake: When Anya was possessed, she cut her right cheek, but in the next shot, her left cheek was cut and she was cutting her right cheek again.
Tabula Rasa - S6-E8
Continuity mistake: In the beginning of the show, Buffy has two necklaces on, one long and one short. However, when Buffy, as Joan, is telling everyone her plan to get away from the vampires, she only has the short necklace on. Then when she is outside, running from Spike, as Randy, both necklaces are back on.
Continuity mistake: When Willow is outside the jail just before she starts pulling bricks out, there are two policemen walking past the open door, but a split-second later as the shot moves out to look up at the window, they disappear.
Once More, With Feeling - S6-E7
Continuity mistake: During the final song, everyone, including Spike, sings "When Does the End Appear?", however, one shot later, Spike is seen starting to sing the word "appear" again and then he stops.
Continuity mistake: When Spike is looking out the window at the demons rampaging in the street outside Buffy's house, Dawn can be standing behind him with her hair trailing down below her breasts. In the next shot, when Spike pulls her away from the window, her hair is pulled back behind her shoulders despite her not having moved. (00:53:10)
Continuity mistake: In 'Flooded', Jonathon reads a few things off the board listing the Trio's ultimate aims. One of the things he reads out is "prototype jet-packs that actually fly", but when the list is shown a few seconds later jet packs aren't mentioned on it. (00:27:10)
Chosen answer: From what we see in the series, certain girls are identifiable as potential Slayers - Kendra clearly fell into this category. The identification method is presumably mystical in nature, but the Watchers' Council are pretty effective at that sort of thing, so they're quite good at tracking down the potentials ahead of time. Not perfect, though - it does appear that Buffy herself may have slipped through the net - certainly she had no inkling of what she was until she'd already taken on the role of Slayer. It is possible, however, that this was actually cultural - an American family would hardly be likely to turn over their daughter to some strange man for 'training', so the Watchers might have chosen to keep an eye on her covertly, whereas some other cultures (like Kendra's Jamaican parents) might be more willing to believe.
Tailkinker ★