User blog comment:Drkdragonz66/Black Ops II - 8 Players and Zombie Story Mode hinted/@comment-199.230.46.145-20120507221451

If they have an 8 player mode, then in the beginning little area of each map, they will have to have twice as many windows, doors, holes, etc., so a group of 8 don't just have a couple people at each opening spamming zombies before they get in. This means that when you play solo, some maps will be exclusively for large groups and ,therefore, in order to make the solo fans happy, some maps will be just for singleplayer, or it will be an overlooked design flaw and will make that one guy run back and forth constantly.

P.S. I like writing long sentences but don't judge me.