Characters can run short sometimes, but it's only ever a temporary problem. If you've just annexed a bunch of provinces and/or created a lot of new armies, your character pool can become empty. Wait six months and it will be full again; guaranteed.IvanV said:No, characters literally run out. Sometimes I don't have anyone to conduct diplomatic missions for months because no one is available. There should be few high quality people and an endless supply of mediocre ones but that is not the case.
The only problem, like cwg9 said, is that occasionally if you've got over a dozen unassigned married women in your pool the game engine thinks you've got enough characters already, even though those women can only be assigned to research positions. But even that problem sorts itself out over time.