His problem is actually insecurity. He portrays himself as this domineering alpha-male, when that's not what happens in the real world. Good leaders command respect, they don't need to tell people how great they are.

He's obviously nervous about his body (compared to other guys), and his voice, so he is over compensating. Luke isn't an alpha male, either, in the true meaning of the phrase. Ben is the most Alpha in there, he exudes that calm presence that doesn't conflict with any of the men, and the women feel comfortable around him.

If you have to shout, you've already lost the argument as far as I'm concerned.