Answer:
Surname of the pilot of the Millennium Falcon.
I can ruin your day, or darken your life. And while I'm expected, I'm never alright. I'm bad for business, and worse for your hair. Wherever I am, there's something not there.
Lighter than what I am made of, More of me is hidden Than is seen.
I grow for a surface, even if you cut me. I continue to grow even after death.
In we go, out we go. All around and in a row. Always, always steady flow. When we'll stop, you'll never known. In we go, out we go.
I go in hard come out soft. Blow me hard and I’ll make a pop.