Because people won't attack it...
My new Lohengrin class Federation Battle Carrier (pic coming soon-I forgot to bring it with me) is a real beauty, with very large weapon space an ample armor and shields. It handles like an Auroran Carrier, but with added firepower in the form of the very destructive Ronginus' Spear. I had flown it throughout the Fed campaign without any problems. And that, my friends, is the problem.
See, no ship would dare attack it. Or, specifically speaking, they only use missile-type weapons on it. No guns, turrets, anything. Even the Raven refuses to fire its deadly CPL on it for fear of scratching its white-and-blue hull. No, the Untargetable flag is off, threat level is 750 and everything else seems to be in good working order. I already dominated Moash space, and no one has yet scratched my armor. Those six carriers could trash my hull any second, and they haven't done anything except send their itty bitty fighters which do all the work of scratching at my shield with their chainguns and sit on the receiving end of 8 railguns and a massive directed thermonuclear beam cannon, without firing their deck guns. Help!