There's Always Something To Look Forward To
Like many shooters, Spec Ops: The Line has an experience-based system for unlocking equipment. As you work your way up the ranks, you get access to new guns, armor, classes and customizable clothes for your character.
There are over 120 customizable helmets, jackets, and other gear to earn as you make your way up the ladder, and that's just the cosmetic stuff.
It's a long and winding road to the top, but once you get there, it's not the end. You can always "Re-Enlist" (think "prestige" in Call of Duty) and earn stuff that wasn't available the first time around.