Continuity mistake: The General Lee is a souped up Dodge Charger, often called a "stock car". As such, it has roll bars mounted inside. Every so often, you see no roll bars in it, meaning that there was more than one General Lee used in the series.
The Dukes of Hazzard (1979)
1 continuity mistake in show generally
Starring: John Schneider, Ben Jones, Catherine Bach, Denver Pyle, Sorrell Booke
The Ghost of General Lee - S2-E6
Continuity mistake: When the bad guys from Sweetwater county try to steal Boss' safe, you see them pushing it up a ramp into the pickup truck. But in the next shot, when Daisy calls the operator, the safe is in the corner. And when Bo and Luke go to untie Daisy, the safe is gone.
Sheriff Rosco P. Coltrane: Ya dun scuffed my ve-hicle.
Trivia: The series' third episode, 'Mary Kaye's Baby', is the only episode of the entire run not to feature the General Lee (instead, the Duke boys drive around in a car borrowed from Cooter).
Answer: Various reasons, but mainly to drive the Dukes out of Hazzard County because the family have been foiling his schemes since his and Uncle Jesse's bootlegging days.
Captain Defenestrator