Can anyone else confirm my suspicions here? I have found that whenever I post a new question, if it is going to receive any answers at all, it will happen within the first few hours of posting. After that, it is too far down the list of new questions for anyone to notice anymore. This is assuming it does not receive any upvotes.
People find questions all sorts of ways, sometimes people find them on the front page. Others use RSS feeds (I used to, back in the day. The value of it is a lot less on bigger sites). Some folks also follow specific tags, rather than the front page to find stuff to answer. I knew of one user who mainly hunted bounties (and that's one way to advertise a question).
Sometimes folks learn something new, and go check for questions that question can answer, and sometimes it'll be years later. While the necromancer badge is for 'late' answers, the revival badge is for first answers that are more than 30 days old - and its a useful metric for guesstimating how many questions get relatively late answers
Its very much about the confluence of the right question and the right answer, and the stars can align, so to speak years later or it might immediately
Of course, if you asked a question, and got an answer years later, it wouldn't do you much good, and you'll feel like you never got an answer when you needed it. It could help someone else though
While it's natural that over time less people will view your question, and thus less likely you'll get a new answer, there are also simple and proper ways to bump the question back to the front page, and this way you get another chance for new answers, as if you posted it in the time of bumping.
The methods for bumping are all explained in How do I get attention for one of my own questions without a good answer?.
The answer is obviously site-specific. I see you're a member of Stack Overflow, and the quote "if it is going to receive any answers at all, it will happen within the first few hours of posting" really does sound like you're talking about Stack Overflow. So I'll base my answer on my experience on Stack Overflow :D
It's true most of the time, new questions get to be on the front page (or close to the front) for little while, and after that they get buried deep, often forgotten forever...
The case is vastly different, however, if you ask a question in a not-all-that-frequent-tag that has at least a few dedicated tag-followers. Those questions tend to get left unanswered for a few hours to a few days, and get answered by one or more of the few tag-followers of the tag.