Why Publish

I've been thinking about this idea of publication and why it's such a popular idea among writers. I made a point in one of my blogs how writing for yourself is important, which is true, but ironic, because many writers are writing for an audience. That knowledge, that someone else will read their words, changes the writing, no matter how much a writer tries to 'write for themselves'. I think the only truly authentic writing may be what we put in our diaries and other places we think no one will see. This isn't a necessarily a bad thing either. Knowing there will be an audience puts pressure on a writer to make their words more accessible, cohesive, and just generally better.
But why do so many people want to get published? There's obviously a certain ego-factor, of testing your writing against the big bad publishing world, but there must something about the idea of other people reading your writing that is enticing. I included publishing in this project because it was something I had never done before and I wanted to try it under some guidance before I was older and without the opportunity to access the resources my Signature project provides. But still, the idea of publishing is enticing to me, even if I don't know entirely why.