Just five months after Rosie O'Donnell launched her new talk show on the Oprah Winfrey Network (OWN), The Rosie Show has been canceled. When Winfrey first announced O'Donnell's show, it was considered a major coup: O'Donnell, after all, hosted one of the most popular daytime talk shows of the past 15 years, and proved to be a ratings boon during her one season as co-host of The View. When The Rosie Show premiered on OWN in October, it earned a modest 500,000 viewers. But ratings quickly plummeted — all the way down to a meager 150,000 viewers a week. On Monday's episode, O'Donnell explained: "I came here to Chicago with the best of intentions, trying to do what I thought would be kind of easy for me… but it wasn't." (Watch the clip below.) What went wrong? Here, four theories:

1. The time slot was horrible
Because OWN doesn't run original programming during the day, The Rosie Show aired in the 7 p.m. time slot, which was extremely problematic, says Ramin Setoodeh at The Daily Beast. "Rosie's core demographic — soccer moms — would be eating dinner" then. And because Rosie kicked off OWN's nightly programming, it suffered from bizarre, underwatched lead-ins that did nothing to help spike ratings, like Who the (Bleep) Did I Marry? and Police Women of Broward County.

2. Changing the format was a mistake
When The Rosie Show launched, it was a pleasant hybrid of a daytime chat show and a late-night comedy hour. As ratings fell, O'Donnell relaunched the program as a long-form studio interview show with no audience — a huge mistake, says James Poniewozik at TIME, because Rosie's most important relationship has always been "the one between her and her audience, not her and her interviewee." Yes, says Setoodeh. The new format felt "like eavesdropping on two patrons having lunch at the Sizzler." Andit stifled O'Donnell's personality, says Mack Rawden at Cinema Blend. She's "always been at her best being zany and goofy," which the format didn't allow her to be.

3. Rosie is just too unlikable
This isn't the same Rosie who cheerily flung Koosh balls into her audience 15 years ago, says Nellie Andreeva at Deadline. The Rosie O'Donnell of 2012 is a more polarizing figure, "with strong political views and an aggressive style." Building a network around such a divisive personality might have been "one of the dumbest programming moves since putting Jay Leno at 10 p.m. on NBC," says Real TV Critics.

4. It was always a poor match
"The network never fit O'Donnell," says Setoodeh. OWN was launched as a vehicle "for inspiring women and helping them better their lives, says Andreeva, which isn't exactly Rosie's style. Plus, O'Donnell was forced to uproot her New York City life and move to Chicago to film the show, "and never seemed entirely comfortable" in The Windy City, says Poniewozik.