I just asked a question on Stack Overflow. Often I notice my questions coming through on the front-page, but this one isn't there, even after I gave it some time. Why is this?
Because the front page contains interesting questions, not the newest questions. Many new questions don't show up on the front page.
You do show up in the newest list (see below), but yours isn't one of the questions that appeared on the front page for me. Apparently front page questions vary from user to user, so others would have seen it there.