Aikidoka do not compete and I think that is a large part of the "bragging rights" issue that some other arts might have.
The next factor is ego, which is discussed here on
Web every now and then. This is a personal issue. Either the person has a "chip" on their shoulder or they don't... its that simple.
Speaking for myself, I am THE MOST humble person that I have ever met or known so, I have no issues with humility. Just ask me anytime!
John "Mr. Humility and proud of it!" Boswell