"Trauma" cancelled

The new fall show "Trauma" on NBC has been cancelled by the network. I don't quite understand why either. It was the most expensive show for them this fall, but it also pulled its weight in viewers, doing better than NBC's 10pm "Jay Leno Show". They cancelled Southland too, which was also by the ER writers, and also was great. While both of the show were a little (lottle) over the top, they were fun to watch, had relatable characters, and kept you coming back for more. Instead NBC has ordered more of "Community" and "Parks and Recreation", both of which are worth a few laughs, but not nearly as many as "The Office" or other triple-A comedies. It seems to me that NBC cancels too many shows, in general, compared to say- Fox. Fox DID cancel Arrested Development, but after 3 seasons, and dwindled viewers. They have kept shows like "Lie to Me" and "Fringe", that by NBC rational would likely be gone. Is NBC really in such financial dire straits that they can't hold on to a popular show for more than one season? Whatever their exact reason, its too bad, I'd like a little more "Trauma" and a lot less "Community".