Check out this video: https://www.youtube.com/watch?v=TFkZ67wnqy0
I don’t always agree with Shad, but I certainly do here. I’ve been reading the comments and I think a lot of them miss what I see as the most important point: character classes don’t just limit the character, they limit the game.
In character class games, only certain characters can accomplish certain things, which is limiting of the characters. But also in character class games, characters can only do what their class is allowed. That’s not entirely the same thing. My concern here is that if no character class has a certain ability, then typically no one in the game can accomplish whatever that task is. For example, before D&D came out with the thief acrobat, there was no way for a character to learn to walk a tightrope, because none of the classes had that skill. And since no specific character class had the ability, it was not accomplishable in the game. It is only in the skill based systems where skills can be used for a variety of actions, some with modifiers, but still, nearly anything can be attempted.
To fight the other side for only a second: There is a piece of character classes that does work for games: ease of learning. For brand new players, an open-ended, skill-based game often offers too much choice. When someone is trying to learn a game, being told, “you are a fighter” is vastly easier than working through “you are a naval soldier, so you can use a crossbow, swim, sail, wear lighter armors, carouse in sea ports, have a smattering of odd languages, ...”.
Early on, one of Legend Quest’s biggest fans told us that while he and his friends loved the game and played every week, he was teach FRPGs to his young sons via D&D, for exactly this reason. I believe he had tried to craft a character for one of them and it got pretty frustrating. But while I will acknowledge this issue, I will also say that it proves that after a while, players and GMs need to go out and get themselves adult games that will allow them to experience role-playing in all its glory.
The secret to making it all work is balance. No one is an Olympic level fencer when they get their first level; they have to build up their skill levels. As long as the cost of those skill levels (experience, time training, etc.) is balanced, the game will be balanced.
Looking for a good skill based game? Try GURPs (at least the original version I played), RuneQuest, and Legend Quest all work really well.