The purpose of topics on questions is to allow people with knowledge about those topics to find questions to answer.
This means the test of whether a topic should be on the question is whether most people with direct knowledge of the topic would find their expertise meaningful to answer the question.
The best answers on Quora are written by people who have direct knowledge about the question. Choosing topics that are aimed at getting questions answered will ensure that the question is shown to the best writers and will get the best answers. In particular, using large untargeted topics often leads to questions being shown to people who don't have the context or knowledge to write the answer that the question writer is aiming at.
More detailed guidelines are as follows:
- Topics should identify the subject of the question. This means that “What is science?” should have Science on it and should not have Scientists because the question's subject is not directly related to scientists.
- People should add topics that are accurate and directly relevant for getting an expert answer to an open question.
- Topics that are only relevant to certain answers should not be added to the question. In particular, potential answers should not be topics on the question.
- For example, if the question is "What are Al Pacino's best movies?", "Godfather (movie)" is not an appropriate topic for the page.
- If the experts from “Godfather (movie)” are expected to answer the question, then the question should be “Is The Godfather Al Pacino's best movie?”
- Excessively broad topics should not be added to questions. The test for adding a topic is "Would the experts in the topic find their expertise useful and meaningful in answering this question?” If the answer is no, then a more specific subtopic should be applied instead. Typically, it might be appropriate to add (1) the most specific, directly-relevant topic and (2) if the specific topic has few followers, one or two more broad topics as well.
- Questions should not be overloaded with topics to increase distribution. As a general guideline, 3–8 topics should be adequate for most questions. Occasionally, a single topic is appropriate, e.g. “What is science?” only needs Science since Science is a topic with an exceedingly large number of expert authors and the more general topics are excessively broad.
- Topics should localize the question when appropriate. When questions have an explicit assumption about a given place, then the localized version of the topics should be used. For instance, “Who is the greatest president in the history of the United States?” Politics should not be applied but rather Politics of the United States.
Quora moderation may take action against inappropriately applied topics. When questions include too many topics, moderation may take one or more of the following actions:
- Questions may be reported for having wrong topics
- People who repeatedly add or remove topics inappropriately may be edit-blocked or banned.