I think it might be because it's become a trend to kill AV off early in order to remove a good player from the board, both from townies and wolves. In addition, there have been times where AV ended up doing all the heavy lifting- my guess would be, she doesn't think it's worth it to put in effort D/N 1.
That or she's got a power that works better if she's lynched/killed earlier.
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Iirc both me and another player remarked on how that may have become a bad habit (getting AV killed early).