Fallout's Character Development System Reviewed

Twenty Sided has put together a short article that details why the SPECIAL, skill, and perk systems worked so well in the original Fallout games.
It's a classless system. You can be a (rogue) or a (melee fighter) or a (gunslinger), but the particulars of doing so are up to you. You aren't locked into choices where being good at fighting makes you bad at conversation, or being good at stealth implies you want to steal stuff. Being classless means it's skill-based. When you level up, your skills improve, not the base attributes. I never liked games where you can become (smarter) or (more charismatic) by fighting and leveling up. Leveling up shouldn't change your core attributes, (or at least, not by much) it should simply allow you to better use what you were born with.

There are seven core attributes in the game: Strength, Perception, Endurance, Charisma, Intelligence, Agility and Luck, which spell SPECIAL. That's clever and makes them easy to remember. Seven is a lot of attributes, but they are clearly delineated and easy to understand. There aren't any ambiguous stats, or stats which overlap. Nebulous, personality-driven concepts like wisdom are left off the list entirely. I've always disliked games where things which should be emergent during roleplaying end up assigned a hard numerical value. How (wise) or (foolish) I am should be determined by the choices I make in the game, not my character sheet.