Underpowered Characters

it is entirely possible that a player will roll up a character that is simply not strong enough to keep up with the rest of the team. This may happen by luck of the draw, or may happen because the player thinks that this will be an intersting role-playing challenge. In either case, the GM must be careful with such players and their characters.

Unlucky Rolls
Players will get unlucky rolls, and unless you are doing a special challenge game where part of the game is that players are to keep the rolls that they get, unusually poor rolls should be dealt with more fluidly. Nobody wants to be the pity character with stats so low that they are virtually useless to the group.

In some games, such as the Palladium system, even characters with poor ability scores can be useful- anyone can use a plasma ejector as long as they have the weapon proficiency. In other games, such as Dungeons and Dragons or the White Wolf games, basic attributes are god. In most of these games, there is an option for point distribution rather than random rolling, White Wolf games tend to use point distribution in favor of rolling. But in those cases where the player has rolled especially badly and the game will be difficult to play with a character given those attributets, it makes sense to offer that character the chance to use the point distribution system as opposed to requiring them to use their rolled scores. This option works better than simply improving the low scores arbitrarily because it doesn't seem unfair to those characters who did roll well. The player in question is also not left with an entirely average character, but can raise and lower attributes as they see fit to make a workable character who is not boring.

Too Much Character in the Character
Players sometimes add quirks or flaws, and often the game includes rules for this, that add personality to their character. Some players however, either because they think it is good role-playing or because they can buy perks with the points acquired from buying flaws, will add too many flaws to their character. The character has so much personality that the result is unplayable.

In order to buy zen combat and improved metabolism and improve three physical attributes, the player has created a character that is agoraphobic and blind. The result being a character who panics as soon as he thinks he is outside. This happens more often in pursuit of character improvements and in this case it is simply a matter of showing the character how limiting the flaws are in game. Often such things can be purchased through actual game play and this will generally satisfy the players.

On the other hand if the player has visions of the masterpiece theatre of role-playing, then they may add flaws for no other reason than to give their character a good back story and some cool motivations. In this case, it is often not hard to lower the level of their flaws to the point where they are story points but do not require game mechanics to be involved. A character may not like dogs because of a childhood incident, but is not actualy phobic. This, you can argue to the player, actually makes it more of a challenge to role-play. If the character were phobic, then the game mechanics would do the role-playing, but at this level it is up to the player herself to make the character show his fear in a realistic and plausible manner.