I think, with Hawthorne in particular, the network didn't do enough PR. Also, I think Jada is a divisive person - people either love her or hate her. I'll admit that I don't really like her. I tuned into that show for Michael Vartan and was surprised that I didn't mind Jada at all.
I still have hope that they will save this show, but shows with better ratings have been canceled. I've given up trying to figure out why networks get behind some shows and not others. I think this show has gotten better over the seasons as it's found its legs. I tuned in for Dana Delaney, but I stayed because the show won me over.