The Dark Age - S2-E8
Continuity mistake: Cordelia tells the Scoobies that Giles was talking to the police about a homicide, but this wasn't mentioned in the time that she was in the room. (00:18:15)
The Dark Age - S2-E8
Continuity mistake: At the end of the episode, Buffy complains to Willow and Xander that she will have to blow her allowance on getting the tattoo removed before her Mom sees it. Moments later when Buffy is talking to Giles, the tattoo is gone. (00:40:45 - 00:42:30)
The Dark Age - S2-E8
Revealing mistake: When Buffy and Giles are talking in the school in the final scene, the same extra (in a beige shirt and blue jeans) walks out of the room behind Buffy twice. (00:42:50)
The Dark Age - S2-E8
Continuity mistake: When Giles is making calls in his apartment, he takes his glasses off and drops them on the desk, just above the notebook with his list of names. But in the close up of the notebook, the glasses are now on the top of the notebook.
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 ★