In the girl at work here - leaving early the first day is not going to make a good impression, but in my head it's forgivable, particularly with advance notice. Heck, coming in late on day 2 is forgivable, with a phone call and an excuse (car trouble? it happens). But both, with no notice and no excuses....forget it.
Someone needs to teach a business etiquette class in H.S., and advanced business etiquette in college. What to wear, how to answer the phone, when to call, etc etc etc. It might help. Heck, just what to wear for an interview would help. I've had kids come in, in shorts, t-shirts, flip-flops, with ear/nose/facial rings, no haircuts, or all of the above Admittedly, it saves me time, in that I just give them a 'thanks but no thanks', but it's still frustrating. It boggles my mind that a person can come to a professional interview in a tank top, and wonder why they don't get hired.