Really - it's a question that I've often thought and wondered about.
Why?? What possessed you to pick up these sharp pointy sticks and try to make something with yarn?
Why do you knit? To make something for someone? To become one of the crowd who have seemed to taken up knitting in the last few years? To find a craft? To take a class on an idle Monday night? To find yourself?
Myself - I started with an ad in the paper. My mom had seen an ad in the local newspaper for a LYS/sewing shop that was offering a class on how to knit, and wondered if I'd be interested. Sure - why not? It sounded like fun. (But come to think of it I remember mentioning something to my mom when I was a kid about learning how to knit. She - not knowing how - told me to ask my Aunt Mary about it. Aunt Mary was, and still is, a very nice woman and I love her dearly but as a kid under the age of 10 still slightly scary. I didn't feel comfortable or dared to say "Mom says you know how to knit. Could you teach me? I mean I only saw her on family get-togethers and as a kid most of your family is slightly intimidating anyway.)
So mom and I took a class. We both got the hang of it for the most part and finished the class. I learned something that could keep my hand occupied while talking or watching bad TV. Being of the internet/information age I searched online for patterns, and found a very easy triangle shawl pattern. Thus the obsession started.....
My mom has been stuck in a scarf rut since we took the class. I did get her to try the skull bag from Hello Yarns (minus the skull). Currently I've got her into the French Market bag from Knitty. She's not as hooked as I've become but if I keep finding ways to kick her out of her rut she could be..... : )