I'm increasingly convinced that business (and life) success is incredibly simple. And that the single, simple key to wealth, success and happiness is getting up early.
It's been almost universally true in my experience that the smartest, most interesting, most creative people are the early risers. And that the midnight oil merchants are arses.
I enjoy playing a little game with people who want to have a meeting (especially when I'm not keen to meet them) I always say let's meet 'first thing' and see when they think that is. Anytime after 8 and they're a lightweight. (I did get into a bit of a game of bluff with someone else once, who was clearly also a morning person and we ended up meeting at 5. But it was the best meeting I've ever had.)
Company meetings, management meetings, status meetings should all be at 7. And then you can have an hour's meeting and do an hour's work before the slack bohemians turn up. And you can leave them mystified when you go home at 4 and still achieve way more than they do.