It used to take a lot less to make us feel heroic. Guns and ships and criminals used to be good enough, as in the stories of Rudyard Kipling, Arthur Conan Doyle, Robert Louis Stevenson, and even James Bond as written by Ian Fleming, not as he's known from movies. In pulps, it was enough to defeat a gang or an unusual villain. The "science fiction" adventure of H. G. Wells and Jules Verne is surprisingly tame by contemporary standards. Now we want everything in movies to be flashy and completely unrealistic, approaching the ridiculous, as in most comic book movies and other action movies (Indiana Jones IV, anyone?).
Jaded: "tired, bored, or lacking enthusiasm, typically after having had too much of something;"
"feeling or showing a lack of interest and excitement caused by having done or experienced too much of something"
We see it in video games: "save the world (or galaxy)" is a pretty common, almost mundane, motivation. It's not enough any more to rescue the kidnapped person or prevent a dastardly deed.
"Saving the world" creates a cheap sense of grandeur. It's the Age of Inflation, everything has to be "stunning" or "awesome," everybody is "saving the world." I call that jaded.
I played in a campaign where, invariably, we faced such waves of monsters that few of us (sometimes only my character) were left standing. The GM evidently manipulated numbers so that this would happen. But it became almost tedious rather than exciting.
We lose impact when it's always "save the world", or always any particular outcome/objective. Pacing is vital both in games and on the screen, and good pacing requires alternate tension and relaxation. If every story is “epic”, epic becomes normal, not extraordinary. If we always save the world, that becomes mundane. Games (like life) benefit from variation in tension/relaxation. The contrast makes them both more intense and more enjoyable. Good pacing would mean alternating the Save the World objectives with others at a lesser scale. (For an under-3-minutes explanation of pacing see https://youtu.be/QAPkcr4b0EE.)
What can a GM do? Set expectations from the campaign beginning. Choose players (and adventures) wisely. Make "Great Objectives" the purpose of an entire campaign, not of each adventure. The threat of death, or of losing all their stuff, should be enough to thrill adventurers without resort to saving the world.
In my campaigns, stretching back more than 40 years, we've never saved the world; an entire campaign might be about saving a city or country, but that didn't happen in every adventure (nor any particular adventure, really). Saving the world calls for really experienced (high-level) characters, and few get that high.
If it isn't enough to risk death, regardless of objective, then there may not be much you can do about jaded players. Or maybe there's no risk of death in your campaign? That could lead to boredom: no extreme lows.
References:
Extra Credits: https://www.youtube.com/watch?v=5LScL4CWe5E
Gamasutra: http://www.gamasutra.com/view/feature/4032/beyond_pacing_games_arent_.php
contributed by Lewis Pulispher