(But do cater to their secret desires.)
There was a time when cutting edge game master technique involved carefully figuring out what general category each of your players fell into, then rating them like a monster so you could understand their vulnerabilities and desires. There’s actually value in that, but on the whole I think its a terrible idea. The value from the notion was it got into what players desired, and admitted that those desires could all be different but still valid, and possibly all fulfilled at the same time in different ways.
Why bother with a clunky label that might lead you to delivering the wrong ‘rewards’ when you can cut straight to the chase and just have that conversation directly? Part of the answer to that is many players don’t know what they want so it doesn’t do much good to ask them. I think most of the ‘noob’ or ‘tag-a-long’ players just want to learn how to play without being made to feel like an idiot or an outsider. Traditional ‘munchkins’ often just want to feel awesome or have better control over their circumstances. Traditional ‘rules lawyers’ usually just want a level set of expectations. Douche bags just want to mess with another player for some reason, and is one of the desires you shouldn’t cater to at all. So rather than trying to pigeon-hole a player and then guess what they want, I tend to just ask. It’s not cheating, honest. And when players don’t have an answer, at least it starts them to thinking about it. Maybe an answer turns out to be wrong. Play and learn.
My one exception is I do try to figure out if players have toys or avatars as characters. A player with a toy might be invested in a character, but it’s more about how far that character can be pushed to do interesting things. If a toy is killed in an entertaining way the player is more satisfied than upset. A player with an avatar has invested some of him or herself into that character though, and if an avatar is killed it is actually upsetting to the player. A miserable toy can be fun for everyone, where a miserable avatar makes a player feel stressed out or attacked. Not that one type is better than the other. A player with a toy can bring buckets of drama and surprises. A player with an avatar can bring massive investment and soul. And again, this isn’t a category for the player, because it can vary from character to character or game to game. but the quicker you figure out which is which the better you can push and break the toys (satisfying that player) and give a safety buffer to the avatars (relieving that player).
A good way to test which is which is to give your players options. Create a drama mine-field. Toys will run to the middle of it as fast as they can. Avatars will stay way clear. That doesn’t mean there shouldn’t be challenge or risk for avatars, but focus the heavy stuff on the toys and let them be a buffer for the avatars whenever possible. Then talk to people. If someone is starting to feel ‘picked on’ push that character more to the avatar side. If someone talks about losing sleep over their character push them way, way to the avatar side. If someone isn’t connecting with their character up their toy factor. Either something interesting will develop from the reaction or the toy will break and the player gets to try something new.