I’ve been discussing the virtues of rolling ability scores versus points-buy, and it’s interesting to consider the reasons people prefer one or the other.
In terms of fairness, players are better served by points buy than rolling. Whereas most rolls a player makes only affect the outcome of a single action, ability scores affect a character over his or her entire adventuring career. Too much is decided by a single incidence of chance. It’s like flipping a coin to decide who gets the best chair in your weekly D&D game* – it’s fairer to flip again each week than to flip once and stick with the result. After all, we don’t force players to roll once at character creation to determine their Initiative rolls, their attack rolls or how lucky they will be when they find magic items. If one single roll has too great an effect, it becomes bias, rather than luck, which is not the effect dice should have.
Points buy is often considered fairer since it gives players a way to compromise between power in different areas. That’s essentially what’s done with other character choices – picking a character class is a compromise between abilities such as magic aptitude and combat skill, and choosing feats is a compromise between which talents you wish to improve upon. Point-buy changes ability score generation from random chance to a kind of resource management, which is a big part of strategy in D&D. It becomes a matter of choice, rather than luck.
Why do many players still prefer to roll their characters, then? A big factor is that when you roll a good score by chance, it’s like finding a piece of treasure. By random chance, it’s possible that you’ll come up with several high ability scores that points buy couldn’t have afforded. Of course, the risk is that you can also end up with low scores. But then, that only make it more exciting. It’s almost a sort of gambling, in that you risk loss for the hope of winning big. The payoff is worth it.
Another reason is that characters come out more “natural” when rolled. Points-buy characters almost always have even ability scores, since an odd score is no more beneficial except when ability scores are used as prerequisites for feats. Points-buy systems usually allow no ability score below an 8 (since useless ability scores would be dropped lower to beef up the good ones), so characters tend to be either boringly well-rounded or all eights and eighteens.
Points-buy: it’s fairer and less open to cheating, but it’s more work and less exciting.
* It is dungeon master’s opinion that the “good chair” is naturally reserved for the dungeon master himself.