Well, for me, it's precisely my serious approach to chess that makes it so interesting and rewarding. If I was ok with just making "any old move," I wouldn't feel as stimulated as I would if I was trying to figure out the best one, whether that's a nice plan, combination, or, usually, a combination (no pun intended) of both. Adding to the stimulation, I also have to think about time, my opponent's style of play, psychology... this is what makes chess fun and engaging I thought.
I also want to point out that, though I like winning, I think the best thing about both players trying to win is that it yields the best, most intense mental battle out of both players.
Stephen_33, thank you! I think you really understood my heart behind the post.
I think we're coming from the same place on this issue. Have you ever heard or read about the anecdote concerning the famous Edward Lasker vs George Thomas game ? You can find it on Wikipedia here...
http://en.wikipedia.org/wiki/Edward_Lasker
It starts just underneath the picture of Lasker & Tartakower. Playing at that level, you can be sure Thomas was as competitive as any player but that didn't stop him being gracious in defeat. I really admire behavior like that.
The game itself is well worth looking at too-Lasker's mate is a real gem!