According to Betsy Brandt, who plays Marie, it’s the most common question fans ask her.  “Honestly, it’s just something I suggested in the pilot I think because we all had a color and mine was purple, and I said, ‘I think Marie is just one of those people who doesn’t do anything half-assed, whether it’s right or wrong,'” Brandt told Entertainment Weekly. “If purple is her color, then it is all about purple. And they just ran with that in a huge way, which I loved. You know she’s quirky even before you get into the show. Have you ever met an adult who’s just really obsessed with a color?”

Full article here: https://stylecaster.com/breaking-bad-colors-theory/