HN in this case is what a salesperson would call an "unqualified lead". A good salesperson tries to make sure that they sell their product to someone who will potentially buy it. Similarly, the person who asks a question should try to ask someone who can potentially answer it. Just as the HN community would reject a posting that is a sales pitch for many products, the HN community will reject a question that is too vague to answer.
For reference, here is the original, way too vague question:
> I want to build a cable company that centers around
> viewer types. Basically, it is my understanding that the
> majority of my cable costs centers around channels
> (like fox) that I just dont watch, if I wanted to build
> a system that let customers limit this, where would I
> get started?
Note that he didn't ask this question on a discussion forum about cable television. He didn't specify if he was looking for advice on the technical aspects, the regulatory aspects, or the business aspects. He didn't hunt around in the user profiles on HN to see if there were people with industry experience that he could approach directly. He didn't describe whether he was looking for high level answers like a list of websites that might have more information, or whether he was looking for very specific info. He did nothing to qualify HN as a good source for the answer to his question.