I didn't believe in the "good physical appearance" and "dressing well" things before; however, I realized these are mostly true. Most of the organizational leaders I've met have a better physical appearance and dress well whenever they are in front of people. These may bring them confidence. That said, "dressing well" depends on the occasion and is subjective, but those people know what to wear and behave.

I also respect the style of Steve Jobs and my bosses, who wear T-shirts and a pair of jeans in the office.