I have been bewildered, a number of times, by the decisions of network executives. To me, they have a really neat and influential job. They get to decide what shows Americans will pick between when they want to spend an evening watching television. There are basically two parts to such a job: 1) Identifying potential shows and 2) Deciding when to cancel a show.
Now, if the same executives are making both of those decisions, then I'm very confused. Every decision in part 1 is a risk. But the person who makes decision #1, if he/she is good at his/her job, must feel confident that it is a risk that will be rewarded. Why would such a person give up on a show before giving it a chance to succeed? Yet many shows are canceled after a handful of episodes (or just a couple of seasons).
To me it seems obvious that a show would need at least 3 seasons to prove itself. An network executives job is to decide what potentially new show will eventually catch on. To cancel it before it has a legitimate chance to catch on is quite absurd. This makes me think 2 different people have these two jobs, but how stupid is that? You hire one person (or group) to make good selections and then another person (or group) to cancel their selections just because they aren't getting extremely good ratings from the gate (and the ratings system, as a whole, is not as good an indicator of what people are watching as they might imagine).
My rule: Give every show 3 seasons. If after three seasons its getting worse in quality and in the quantity of people watching it, then you're executive(s) made a bad decision to which they should be held accountable. But by no means should a network cancel a show before it's 3rd season. That's either not showing enough confidence in your highly paid employees, or dividing up your employees against one another.