Not sure I can be any clearer or how many times I have to repeat. XP, gold for XP or any variation therein is metagame motivation, it's motivation for the player not the character. When I DM I want the motivation for the player to be playing a game that they enjoy, I do that by creating motivations for the PC.
I'm well aware of the reward centers of the player being rewarded by leveling up. I did not make myself clear. I was discussing what would motivate some farm kid to pick up a pointy stick one day and say "I'm going to go risk getting my derriere handed to me by goblins! Later my dudes!"
No one in this thread - me,
@hawkeyefan, @ Aldarc,
@EzekielRaiden to whom you replied with your post about D&D having no rules for player goals, anyone else - thinks that "XP for gold" is a character motivation.
Character motivations can be anything at all. Or none - a lot of classic D&D has been played using characters who have no motivations at all, but are just playing pieces (eg I ran a session of S2 White Plume Mountain earlier this year that was as I've just described).
I also note that you say
when I DM I create motivations for the PCs. That's interesting. I started a thread earlier this month on different ways of establishing starting situations and motivations:
Various ways of setting up and starting RPG play What you describe is an example of category D in my thread. One reason for having different structures and processes of play in a RPG is to open up some of the other possibilities that I described.
I would not know how to run relatively complex combat without the rules. You could have one person point and say "Bang your dead" to which the target says "Nah uh, I ducked". If I wanted a simplified system I could play rock paper scissors with my players. Another option would be to have the attacker roll up to 3 6 sided die if they have the resources while the defender rolls up to 2 6 sided die to defend if they want to risk that many resources and they're available. But I was discussing the somewhat complex give and take combat represented by D&D, not Risk.
When a player says (speaking as their characer) "I jump the pit", presumably you don't just say "Nah uh, you fall your doom!" Or if they are in a running race against a NPC, you presumably don't just say (in the voice of the NPC) "Huh, suck on that, you lost!" Presumably you call for opposed checks, or checks against a DC that reflects the difficulty of what the PC is attempting, or whatever. Combat can be done the same way. You prefer to do it a different way (and dismiss other approaches as "playing Risk") but that other way is not
needed. It's an option.
I don't know how you do resource depletion when a PC jumps a pit or talks to a sentry, but however you do that could be equally applied to combat resolution (eg in Prince Valiant, the RPG I mentioned upthread, the GM decides:
RPG combat without injury and healing rules).
D&D is not a particularly accurate simulation of combat (and an accurate simulation would probably not be particularly enjoyable) but there it's there at least in broad brushstrokes.
I don't follow this. Where does simulation come into it?