Brawl is rage incarnate. It's not that he doesn't love his job -- he does -- it's just that he has so little control over the destruction he brings to the battlefield. His rage is so great, it's been suggested that when he combines with his fellow Combaticons to form the left leg of Bruticus, it's his rage alone that fuels the titan. But fortunately for Brawl, he has no problem with this. Best to love what you aren't capable of controlling in the first place, eh?