You've got 10 characters to reach max level with. You can consider that a personal achievement.
I'll have to say though, Call of Duty was smart with implementing "prestige mode" because it requires so little effort to develop and yet it seems to give players much more motivation to keep playing.
It is kind of an illusion of progress indeed, but it does keep the player engaged and that's the important thing.
not completly wrong or right.
i am still going in prestige modes to get the highest medal and the highest camo styles and stuff.
+ it's more a challenge to own the players who turned highest level at the start, and don't get prestige. or got it with cheats.
just like CoD Modern warfare 1. first one with this method of playing. i owned almost everyone at 1 of the biggest indoor LAN in europe, as a lvl 1 person. with only standard load-out.
either way you can play, or you can't. just need to keep practicing