But the very fact they're forming an opinion about the series future based on two episodes worth of ratings is stupid. They should present this kind of information in a clear and unbiased way.
No, it isn't.
Sorry, but most shows that put up a two episode performance like Constantine has have been cancelled.
Look at what happened to Dracula
Episode 1: 1.80 18-49 rating, 5.26 million viewers
Episode 2: 1.28 18-49 rating, 3.39 million viewers
Compared to our Constantine
Episode 1: 1.40 18-49 rating, 4.26 million viewers
Episode 2: 0.90 18-49 rating, 3.06 million viewers
Now consider that Dracula was co-produced by NBC and a British company, based on a public domain novel. Constantine is produced and owned by one of NBC's biggest rivals (Warner Bros), and has much more in the way of special effects.
Hannibal and Dracula are both produced under a unique deal that costs the network much less than other original drama series. Hannibals license fee is set to go down for season three so the network ultimately decided to renew that show and cancel Dracula.
http://tvseriesfinale.com/tv-show/dracula-tv-show-cancelled-by-nbc-no-season-two-32514/
Dracula did better ratings, was cheaper to produce, and still got cancelled. And Constantine is dropping much faster.
You're just emotional because you like the show, and won't read the writing on the wall.
It isn't their job to get people to watch a TV show. It's their job to predict what's going to happen based on the data available, and that's what they're doing. They've been wrong in the past, and they openly admit that, but they're right the overwhelming majority of the time. And they're right this time.