Diminishing returns (DR) refers to the mechanics used to prevent bots and exploits from disrupting the economy and gaining an unfair advantage over legitimate players. There are several types of DR in the game, each of which is character-based with the exception of dungeon DR, which applies to the entire account. Although DR could affect most activities that have potential for abuse, very few players will experience it during normal play.
DR is needed for dungeons due to their large rewards and ability to be repeated quickly. Similarly, it is applied to Dynamic Events to limit players from exhaustively farming one area, reduce congestion in one particular map, and to discourage illegal activities such as botting.
- Dungeons, in which the completion rewards for an account are cut severely after the first run for each path.
- Open world:
ArenaNet has never shared the precise details of how diminishing returns is implemented in Guild Wars 2, with the exception of dungeon reward DR. From various posts by the company's staff, players have pieced together the general concepts:
- The longer a character remains in the same area, the more likely it will trigger DR.
- Once triggered, the impact of DR will increase over time.
- The only way to "remove" DR is to move the character to a new area for a period of time, believed to be about 15-20 minutes.
Dungeon DR reduces the completion rewards for completing the same path more than once. Unlike other forms of DR, dungeon DR is account-based, meaning it cannot be avoided by running the same path on multiple characters. It works in two ways:
- The bonus reward (40 tokens and ~1 –3 ) is only awarded once per path per day, resetting at the same time as the dailies.
- Completing the path consecutively or in less than 30 minutes triggers a second type of DR, which reduces the base reward for that path by half until reaching a minimum value.
- Affected dungeon rewards
Open world DR
Open world DR is area specific, i.e. it triggers after a character passes a set limit of events, believed to include cycling through events on a map for over three hours or remaining within a narrow portion of that map for similarly long periods. Event rewards and loot will often show a dramatic decline after hitting this limit. Unlike dungeon DR, open world DR is character-specific and can be removed by switching between characters.
- Affected dynamic events
- Originally, DR was character-based in dungeons. 
- ^ https://forum-en.guildwars2.com/forum/game/gw2/Let-s-Start-the-Karma-DR-Dialogue/page/5#post338355 Jon Peters, GW2 Forums
- ^ John Smith posted that, "There’s virtually no DR active on any given day."
- ^ https://forum-en.guildwars2.com/forum/game/bltc/Stealth-nerf-on-ecto-drops/first#post693957 John Smith, GW2 Forums
- ^ https://forum-en.guildwars2.com/forum/game/dungeons/Dungeon-DR-is-now-account-bound-never-got-it-before-today/first#post319465 Jon Peters, GW2 Forums