Each player will have his own idea of what it means for his PC to 'win' or 'lose.' The player must decide for himself. If he aims at making Admiral in the StarForce, that is the chief priority in his PC's life, and the PC will conduct himself accordingly. If it is to have his own StarShip and to set out on the life of a Free Trader, well and fine. But there will be no 'easy' measures of superficial 'success' like experience points and experience levels. Success is something that satisfies a person at the moment. There are always new horizons, new worlds to see and win, new adversaries to best in combat or hard trading, new adventures to excite one and make life worth living. He will likely get there too, if he is competent.The italics above are mine to emphasize the most immediately interesting thing the cited paragraphs, namely that Space Opera has no mechanical system of character advancement, aside from in-game training, which is both time-consuming and potentially expensive. Traveller employs similar assumptions, as did many Basic Roleplaying-derived RPGs to some extent, but there's no philosophizing to justify the design decision. Having played a lot of Traveller, I've never had any problems with the idea characters who didn't improve mechanically much over the course of play or who did so at a glacial pace. In fact, as I get older, I find I like the idea more and more, although, like all such things, I don't think it's appropriate for all game systems. I think a more generalized XP system works well in D&D for the most part, given its literary inspirations.
We suggest that players try to get rid of the hyper-competitive spirit that marks some kinds of role gaming. The measure of a character is whether or not the player gets him to the goal that the player/character sets for himself. Then, having attained that goal, the way is opened to 'retire' from the game and start a new character as a replacement or to seek still greater goals.
One wins in role-play in the manner that one 'wins' in life -- you get to where you are going. And that can include a lot of living a lot of countryside!
I am amazed, though, how commonly used D&D's approach is. Most RPGs I've played use experience points that can be applied broadly without regard for how the XP was gained. It's a conceit of gaming I'm more than willing to accept, but, when you think about it, how much sense does it make that a character should be able to use XP gained from an adventure where he spent most of his time fighting evil wizards to raise his skill in, say, diplomacy? Or better yet to suddenly manifest the ability to pilot a boat? It becomes even more bizarre when you factor in things like "story awards" or "roleplaying awards." Again, I understand the logic behind such things, but, if the bonus XP you get from skillfully portraying your character as a conflict-averse nebbish can be used to gain fighting skills, then, really, what's being rewarded here?
I'm starting to ramble already, which just goes to show I'm not entirely sure what makes for a good experience and advancement system in a RPG. I can only say that, from a "realism" perspective, limited and slow advancement based on actually practicing the skill in question (or studying) makes the most sense to me. Most other approaches strike me as game artifacts, none of which inherently make more sense than any other. I often see D&D's XP system lambasted as "illogical" and, in truth, there's some weight to that criticism. But it's a criticism that rings pretty hollow if one's own preferred system gives XP for "good roleplaying" or "number of hours played per session," to mention just two types of alternate XP awards I've encountered.
All this makes me wonder why more games haven't adopted something like the systems in Space Opera or Traveller. Why do we need XP and advancement at all?