So, I thought about why I have liked or haven't liked certain shows and decided to write a list based on factors that make me turn on or turn off the television. (mostly I turn it off nowadays)
I chose three factors: premise, characters and storylines. Those should be enough, I think.
There are different kind of premises. Some are more intriguing than others. Simple usually works. Prison Break for example was about a guy trying to free his (likely) innocent brother from jail. A simple premise and it turned out that the first two seasons were pretty awesome television.
Another show that had an interesting and simple premise was 24. At first I didn't believe that it could work but it turned out that I was wrong. Things happening in real time was rather interesting after all. Jack Bauer trying to save the day.
Or how about Lost. An airplanes crashes in to the sea and the survivors have to learn to live on an island that they know nothing of. Simple and pretty interesting.
However, there have been cases in which I have thought that premise was pretty uninteresting and not compelling at all. For example, Flash Forward had a premise that... ..I mean, wasn't the premise about different people seeing things happening ahead of time and then basically living with that knowledge? Well, I can't remember anymore. It wasn't simple and it didn't work.
Another factor that is important to me are the characters. It's a good thing that they are likable. For example, I have pretty much always liked characters on David Kelley shows. They're likable, interesting and relatable. They're trying to do the right thing. Except for the villains of course, but let's face it, you need them too.
Another example of likable characters is for example The Big Bang Theory. We had the nerds who were intelligent and yet pretty clueless about how they or we are supposed to act in 'our' society. This was a great show until the characters started to change and became less likable.
Characters don't necessarily have to be that likable in order for me to like the show in question. For example, The Shield had a main character, Vic Mackey who in the pilot (I think) shot and killed an innocent cop. Not a good start. But rather quickly the characters became relatable and even though these were so called dirty cops, you were rooting for them.
At the same time, it doesn't really work for me if the characters aren't relatable. For example, I could not stomach Sopranos. I could not understand why someone could buy Tony Soprano first killing some guys and then going to see his therapist and talk about his issues. To me it was just too implausible.
Last, but not least we have the storylines. Storylines are based on characters and the premise, which is something that people in the industry don't pay enough attention to nowadays. (it seems that anything goes) They expect that the show works no matter what they do.
Yet, even though a premise sometimes isn't that great and the characters itself aren't that interesting, the show can still be good. Characters and premise are important but you can still sometimes do miracles if you're a great writer.
Seinfeld and Curb Your Enthusiasm for example didn't have a great premise or that likable characters but they were both pretty good shows because both were (Curb still is) professionally written. So it can be done. As long as you know how to tell a story.
But just because Larry David has been successful doing it (I don't have any other examples), you probably shouldn't push your luck. The risk of having no likable characters and no good premise probably won't do you any good.
Well, except in Hollywood maybe. But still, shows are about premises, characters and storylines. If you don't pay attention to the first two, the chances are that you're screwed no matter good you supposedly are as a storyteller.