I think she'll "re-emerge" at some point, as well. Probably with the same or similar marketing scheme that LR has erected for herself. She (Lisa) very likely makes the same (or more) kind of money that she did when she was a host, without the pressure of having to keep her sales numbers up. Not to mention being harassed and stalked.
I think that Jill would still be working at QVC had she did something similar to what Leah did, which was to reinvent herself. Leah's weight loss was quick and dramatic, and now look. Not only is she still at "the Q", but she's been given another timeslot hawking fashion and beauty products.
Jill could've/should've done the same thing. She could've gone on NutriSystem, announced it on air and even done a "weight-loss-along" gimmick, inviting viewers to sign up on a designated Fb page carved out just for that, to provide tips about using the program, exercise and wellnes, maybe even included an exercise apparatus or two, (like doing quick videos on the AeroPilates machine...Marjolin isn't on QVC anymore due to "soft sales", or the exercise bike, something of that nature).
Oh well. Anyway, I think that she left because either: 1. she didn't get a new contract offered or 2. the contract she got was for a lot less money, and she walked. Whatever she's got planned for her "second act" as David Venable called it on her swan-song finale, I hope she does well. Nothing succeeds like success.