Why do people make viruses?

Apart from spyware (that could capture credit card details) what is the point

Why do people make viruses?computer security

It is interesting, with all the training and knowledge necessary in becoming an IT professional, the number one question I receive is; "Why do people make viruses?" This always makes me wonder if FBI profilers are ever asked; "Why does my computer have so many pop-up ads?" And of course, computer people often ask each other: "Why do people think they need more memory with their hard drive is full? And why do they call their computer case a modem?" These are all important questions, but only one of them I am qualified to answer. I still try to answer the other to the best of my knowledge. Unfortunately, the best of my knowledge is very, very, unpleasant.

I used to answer; the reason people make computer viruses is because they have no control in their real life's and compensate by creating their own "control". Now, I just sum the entire answer up with, "because they have small penises." I usually get a knowing nod, and some even reply, is that why there is so much spam on how to enlarge one's penis? Yes. I answer. The government floods the Internet with penis enlargement spam, in an effort to control viruses. I usually close the conversation with, "I'm not an actual mental health professional, but I did stay at a Holliday Inn Express last night." And because no one else seems to have seen this Holliday Inn commercial but me, there is a brief awkward silence, and they walk away thinking what a geek I am...I do it to myself.