pyschological key to poker?

[Kenshin]

Hi all,

I must first preemptively apologize if you either consider this post redundant or find survey-type questions boring.

Which psychological element of poker do you believe is the key to successful play?

Obviously I cannot truly distill a game as complicated as poker to a single trait; however, I would claim patience is the key to limit poker.

The ability to fold 2nd pair to a raise from an obvious player or to muck Q8o on the button after being cold decked for 2 hours represents an essential skill derived from patience (IMO).

Kenshin