Anyway! Obviously it's not true for something like Gamma World, but I decided that as a fun thought experiment, I'd try it with the characters from the Revenge of the Giants game, colored with some observations from other campaigns we've done or just things I've noticed about the player in general. I'd be curious to know how close I got to what the players themselves think on the subject.
...is the easiest. His character is a heavily-optimized crit-monster with a lot of armor and a big sword. He wants to cut shit up, suck up damage, and end each fight with 2 hit points left out of the billion he started with. This isn't to say his character has no personality, being a fresh-faced prodigy just out of training who goes "Wooowww!" at everything new he sees. But still, this is not a subtle character designed for a lot of intrigue. To make him happy, I need to throw big monsters at him that will chew him up, and be chewed up in turn. This has been a fairly consistent pattern with his characters (Dragor the fighter/barbarian, Balgor who was basically Dragor II with some variations), although he has done the occasional backstabbing thief or power-hungry wizard. Mainly he seems to want to be where the action is.
...is a little harder to peg. In this game she's playing a sorcerer whose main activity has been to blow things up, which is fairly atypical of her usual character type. She is usually much more subtle, being fond of mind-tricking Jedi characters or investigative types. That said, she has also played the butt-kicking barbarian more than once (going as far as once having a character named "Rage," whose catchphrase was, "Come back, I want to kill you some more!"). In this particular instance, my guess is that she figured D&D tends to be a fight-heavy game, and so came up with a character who would be useful in that context without requiring more system-mastery than she wanted to deal with. (She's a big fan of more rules-light games.) She seems to be content with whatever is going on as long as she gets to contribute a bit, so to keep her happy I basically need to make sure she has something to do without requiring too much mucking around with the rules.
...likes outliers. A human fighter would bore Sirfie silly, especially when the option of playing a wereshark druid might be on the table. In this particular game, he's playing a gnoll cleric of a NG deity. Some of it is just a penchant for eccentricity (Sirfie really wants to be playing a Discworld RPG, but takes D&D because that's what's going), and some of it is because he is a brainy guy and needs the mental stimulation that comes from playing a character with a lot of moving parts or who can shift quickly as the needs of the scenario change. More than any other player in the group, he is willing to step up and be the face guy ... I don't know if that's because it's a role he actually enjoys, or because he senses that's what's needed and configures his playstyle to suit. (The only other face guy in the group is me, but I'm usually the GM.) To keep Sirfie happy, I need to give him lots of plates to spin at once (such as varied encounters that have multiple simultaneous goals), weird "what-the-hell-is-that" critters, or puzzles to take apart and figure out. The occasional mind-boggled muggle reacting to his oddness is probably welcome, too.
...is somebody I've been playing these games with for close to thirty years, and think I may just now really be starting to figure out. His current character is a ranger/rogue with a lot of archery, high saving throws, and evasion. Comparing this with some of his previous characters, such as the summoner wizard who threw "our monsters" at "their monsters" like a Pokémon trainer, or the burglar who learned just enough magic to cast sleep spells on anyone who woke up while he plundered their house, and I start to see the pattern: "Don't hurt me!" It's not cowardice — he'll rise to the occasion and find some way to achieve the stated goals of the party — but it is definitely timidity (which, given that he is a mouse, makes sense). To keep him happy, I've got to devise big, scary things between him and his goal which he can then find a "safe" way around, or at the very least that he can find ways to defeat without getting chewed up himself (as opposed to jamesbarrett, who loves being chewed up). Paradoxically, this also requires occasionally getting caught out in the middle of the spotlight with the alarm going off, so he can frantically find a way to scramble to safety in the midst of a disaster (such as dodging the dragon's fiery breath).
Whattya think, folks, sound accurate?