Danielle LaPorte asked the burning question "What do you suck at?" A GREAT question!
For me there are a few answers. I'll get the ball rolling and ask you to throw in your three cents as well....
I suck at accepting praise. When someone compliments me, I give them every reason in the book as to why "it" happened but I'm not a part of the equation. I have to learn to say thank you.
I'm horrible at delegating. I eliminate delay in all its forms (whenever possible) so have a hard time waiting for someone to get something done.
I'll add to this over time.
I live by "When at first you don't succeed, try something you've already been successful at and become masterful at it". That frees up others to step up and show their mastery in areas where I suck. Thus a great partnership or team is formed!
What do you suck at?