I think a good friend to me is all about trust and loyalty. You don't ever want to second-guess whether you can tell your friend something.
There is never just one thing that leads to success for anyone. I feel it...
The betrayal of trust carries a heavy taboo.
If there is any one secret of success it lies in the ability to get the other person's point of view and see things from that person's angle as well as from your own.