Again, he did it again!
This student, whom I have encountered twice before showing disrespect for my time, turned up again, knocking on my door. He happened to catch me at a bad time when I had a lot of urgent work I had to do and no I couldn't spare 5 mins or 30 mins or however long it was going to take to help him, RIGHT THEN.
That's not what I said to him though, I was very polite. I reminded him of the notice on my door that not only explains when my office hours are (he did not turn up during office hours) but also explains that at other times students need to make an appointment because I can't guarantee to be available. I explain that I was busy at that time and he needed to make an appointment.
He did not accept this. He didn't take on board what I'd said about being busy and not having the time right then at all, and continued to ask (nay, demand) that he get to speak to me right then. I replied again saying that I'm sorry, I'm busy, and he was still demanding my time as if he thought that just because I was in my office, that means he got to choose how I spent the next few minutes.
After repeating myself twice, I snapped at him: "I said, I'm busy!" and immediately shut the door. He immediately starts banging on the door and shouting. I don't know what he did after that, because I put my headphones on along with some loud music, and got on with my work.
Later on I sent him an email explaining carefully that he needed to show more respect for others' time. Just because he might have something important to deal with at a particular time doesn't mean that other people don't have anything important to do at that same time. Let's hope he learns the lesson that you can't force other people to give you what you want, when you want, just by disrespecting their time.