Continuity mistake: After Bill shoots the fruit in the truth serum scene, there is a tented fold in the couch's fabric, to the right of Beatrix's right shoulder as she begins scooping fruit from her chest. Then it's gone. Tented fabric reappears. Then is gone again.
Continuity mistake: When Beatrix confronts Bill in his hacienda, the Kashira (the end cap) and the Fuchi (the collar below the handle guard) on her sword are silver. The Kashira and Fuchi on Beatrix's sword are black.
Continuity mistake: In the Face-to-Face chapter, Beatrix walks into the apartment wearing a black leather jacket and a blue dress. Later, after recalling the time when she found out she was pregnant, they show her standing in the doorway to the backyard wearing an orange shawl which didn't appear prior to that shot.
Continuity mistake: When The Bride reaches for Bill's sword, he shot the TV to stop her. The next time the TV is seen, there is no damage at all.
Other mistake: At the very end of the film, when Beatrix kisses B.B. in the motel room, B.B. looks very briefly at the camera before the two of them smile in the direction of their television set.
Chosen answer: The way she talks to Budd as he lies dying, seems to indicate that she has disliked and hated him for years, plus the fact that she feels that he was not "worthy" of killing Kiddo (seeing how Kiddo was a fantastic warrior, while Budd is an alcoholic hick). However, it would be difficult for her to get close enough to kill him earlier, as he would not buy any excuse why she just came visiting. But when Budd actually invites her over, she gets a chance to get back at him, and in the same while take the credit for killing the Bride and retrieving her Hanzo sword for Bill. Vengeance and personal gain in one swoop.
Twotall