Maintaining Balance (DMG)

For all his good intentions, sooner or later the DM is likely to err in the awarding of treasure. Either he will award too little or hand out too much. The first is just tight-fistedness; the second leads to high-powered, low-role-playing campaigns (sometimes called "Monty Haul'' dungeons).
Now, if both DM and players enjoy a particular type of campaign and are having a good time, there is no problem to fix. However, more often than not, these two extreme adventuring styles lead to game problems.
==Too Little Treasure==
In the case of a tight-fisted DM, the most obvious signs that the players are not having fun are frustration, cynicism, and low expectations. If the characters are not finding treasures commensurate to the risks they took, the players are going to wonder if all the effort of playing is really worth it. They become frustrated when, upon solving a devious trap, they discover a pittance, or nothing at all.
Their cynicism shows as they start to make snide remarks about the level of rewards they have received or are likely to get for future efforts. Finally, they just begin to expect less and less from the DM's campaign, until it reaches the point where they expect nothing and they go home! In such a campaign, the DM may have a fine time, creating detailed settings and elaborate adventures. But if he does not have the enthusiasm of his players, there isn't much point in playing.
Such a campaign can succeed if there are other rewards that involve the players in the game. Perhaps there are ample opportunities for character advancement or personality development. The characters may have the opportunity to play a decisive role in world affairs. These things are possible, but only a DM of extraordinary skill can overcome the drawbacks he has created.
Fortunately, the problems of too little treasure are easily fixed—simply introduce more treasure into the campaign. No adjustments need to be made to the characters. The treasures available in the game world can be increased without the players even aware that the change has been effected.
==Monty Haul Campaigns==
At the other extreme, the problems of too much treasure are not so easily solved. Here players may enjoy the gameóand why not? Their characters are doing quite well. They have sufficient money and magic to best any situation the DM can devise.
However, the DM seldom has the same enjoyment. He is faced with the task of topping the last lucrative adventure. He must make each adventure a greater challenge than the last. While this is true for all DMs, it is grossly exaggerated for the DM who has given out too much: How do you top the adventure where the fighter got the Hammer of Thor or some equally valuable item?
Invariably, the players reach a point where they, too, become frustrated. Everything is the sameó"Oh, we did this before," or "Ho-hum. Another Sword of Instant Monster Destruction." Soon there are no challenges left, because the characters have earned everything in the book!
Fixing such a situation is far from easy. The first thing to do is to stop giving out so much treasure in future adventures. Even this isn't as simple as it sounds, since players have already had their expectations built up. Imagine playing for months or years in a world where you routinely find 5 magical items and tens of thousands of gold pieces each adventure and then, one day, finding only two or three magical items and a thousand gold pieces! Still, painful as it may be for players, cutting back on future treasure hauls is a must.
The second part of the fix is far more difficultóremove from the campaign some of what has already been given. Most players won't voluntarily surrender their goods and equipment just because the DM made a mistake. The inventive DM must be inventive, resorting to new and bizarre taxes, accidents, theft, and anything else he can think of. Use a given method only once and be sure to allow the characters a fair chance. Nothing will upset and anger players more than having their characters jerked about like a dog on a chain.
Sometimes the situation has just gotten so far out of hand that there is no way to bring it back under control. For example, because the DM has given out excessive magic, the players have near-godlike powers. They have used wishes to exceed ability score limits and enhance their classes with permanent abilities. They have fashioned other-planar stronghold impervious to anything. They have reached the point where they are dictating the structure of the game to the DM. There is only one cureóstarting over.
Require all the characters to retire, and begin anew with 1st-level characters, being careful not to make the same mistakes again. The players may grumble and complain, but if the DM is fair, the complaints should eventually be overcome. To this end, the DM may even want to set the new characters in a different part of his campaign world, one that has not been explored before.