a) so that they are an accurate representation of my personality
b) to be sure no child/slave labour was involved in their production
c) because it would just be cool, and other reasons like fitting well and being available in the colour of my choice, control costs, not see everyone in my town wearing the same things etc. etc. etc.
Trouble is, I can barely sew. Do any of you lot make your own clothes - how did you get started?