Some computer games have an addictive quality which comes from having many “achievements”, frequently reminding players of their progress. Each new achievement gives a sense of accomplishment for the player, and since the steps are relatively minor, the next reward is just around the corner.
The term “gamification” applies when a large task is broken into many relatively minor, achievable goals which are salient in the form of points or trophies. We might ask if successful crowdsourcing requires gamification; for instance, is Wikipedia gamified? The answer is actually not straightforward.
The attraction of gamifying a task is that it may take on the addictive qualities of a game, getting contributors to put more effort in by making them feel more rewarded. This reward might be a personal sense of achievement or the social value of showing off the badge.
A down-side of gamification is that it can potentially ruin motivation. A person’s motivation can be intrinsic (doing the task for its own sake) or extrinsic (based on external incentives such as pay or prizes). A well-replicated finding in psychology is that extrinsic motivation decreases intrinsic motivation. In other words, if someone is already enthusiastic to contribute, heaping them with prizes and incentives will make them less likely to contribute, or do their best work, in future.
Incentives seem to draw attention to themselves rather than to the benefit created by the work. Contributors may come to see themselves as working for the incentives rather than for the good of the work itself and its outcomes (Sutherland, 2007).
Extrinsic motivation can also create perverse incentives: when people are rewarded for their number of contributions, or for other achievements defined by the software, the actual quality of the work may be sacrificed. This happened for the citizen science project Galaxy Zoo when it introduced a score and other gamification. When Galaxy Zoo introduced certain game-like elements, like a score, they found that the quality of results dipped.
"In the early days of Galaxy Zoo we did have a ranking system [for top contributor and so on], but it led to people being careless with classifications, unhappy about their position, suspecting each other of somehow cheating etc. So things improved without it."
Galaxy Zoo forum moderator