In Top Chef Season 1, Cynthia left because her sick father had taken a turn for the worse, which is how Andrea returned after being eliminated.Originally Posted by Poppy Fields;4079109;
In S2, Mia quit at judges table rather than see Elia eliminated for the holiday catering challenge. This was after having a long fight with Cliff, who kept throwing her under the bus while he had immunity.
In S3, Howie tried to quit during judging, but the judges wouldn't let him, and then eliminated him anyway. (He just wanted to be spared the verdict.)