Expand?
I was always more of a night owl, but working the night shift for several years broke me. If I could, I'd never go to sleep... that still happens sometimes, where I stay up so late the sun comes up and I decide to try again tomorrow night.
I'd probably do ok working noon-ish to 8-ish. But mornings, even starting at a relatively late 9am, is a killer for me most days and really hurts my ability to get a full night of sleep.
I say it's my fault, because there is no reason I'm saying up this late, I just never decide to end the day and go to bed.