Continuity mistake: Near the start of 'The Wish', the scene where Cordelia is talking to the Cordettes and meets Anya. During the close-ups of Harmony, Anya is standing to camera right of the brunette Cordette behind her. A few seconds later when the shot is further away Anya is standing camera left of the Cordette. (00:05:40)
Visible crew/equipment: Just after Cordelia says "let's go to the Bronze", check the top of the screen - a microphone drops into shot for Harmony's line "is that a joke?" (00:16:20)
Continuity mistake: When Buffy is walking forwards through Angel's dust in 'The Wish' there's a vampire running towards her, only a few steps behind. Then there's a shot of her walking forwards taken from another angle, then when we can see behind her again the same vampire hasn't moved forwards at all, he's still running from 3 steps behind her. (00:41:25)
Continuity mistake: At the beginning of the episode when Buffy is fighting the demon, she stabs it and the demon lands half on top of her. When they fall to the ground, you can see a big stain on her pants where the demon touched her. But when she stands up, her pants are clean.
Visible crew/equipment: There's a boom mic visible when Cordelia is talking to Harmony and the other Cordettes. It's the first scene in the alternate universe and they're standing inside a classroom of Sunnydale High (Cordy says something about going to the Bronze).
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 ★