Because they are (top to bottom):
-Emma Frost, head rich bitch of the X-Men, former villain and a side-effect of her power to turn into diamond renders her emotionless.
-Cyclops, leader and now effectively war general of the X-Men, forced to make decisions to save his species that have moved him past his old less aggressive/hard outlook
-Namor, King of Atlantis, always characterised as stuck-up and disgusted by the prescence of "surface dwellers", and recently conceded to join his fellow mutants in the X-Men, reluctantly not in a leadership role.
-Magneto, formerly the X-Men greatest foe, a man of grandiose ideas and schemes who used to want nothing more than every human on earth to lick his boots clean.
They're the Plastics the X-Men.