For the eight seasons of Bewitched, Darrin Stephens had multiple secretaries played by different actresses. One of them was Marcia Wallace, who would go on to lend her voice to the Simpsons’ teacher, Edna Krabappel. Continuity was not the strong suit when it came to his secretaries, as there were ten different actresses playing the part.
Funny enough, even though there was no reason to cast them as the same secretary, each actress played the role of Betty. So according to IMDB, Darrin had ten different actresses playing the same secretary. That makes sense…I guess? Looks like Bewitched didn’t learn its lesson about recasting.