why do we blog?

i ask this of myself a lot and jenna park of sweet fine day really puts it beautifully in her post. i'm not promoting a business but i do use it as a "creative" release. it's also a nice snapshot to remind myself of what i've done. i'm often referring back to posts for travel recommendations or exhibits i've viewed. i'm not so sure how much of a community i've garnered since i don't get many comments though my friends say "i read it on your blog." that brings a smile to my face. i don't really write a lot. i think i've grown lazy and posting a pic or song seems to say a lot, no?