The Dead Mixer wrote:
I recall reading that behind the scenes, she didn't get along with Stewart, and as he was the series lead, that put the writing on the wall for her....
I'd heard that Diana Muldaur did the series as a favour to Roddenberry, and never PLANNED to do more than one season, hence the "Special Guest Appearance" status rather than being listed as a regular. I don't think she made it public at the time that she only planned to do one season though.
Truthfully, I suspect 'the truth' fell somewhere between all these claims:
* The character was not being that well received by fans
* Maybe some of the cast/crew didn't get on too well with her (Marina Sirtis has been bitchy about her since at conventions, but then Sirtis is bitchy about pretty much everyone who isn't in her 'cool gang')
* With Maurice Hurley gone, Berman and others who were always fond of McFadden saw a chance to bring her back
* Muldaur didn't really want/plan to stay long-term anyway