Comments will be removed under a few circumstances:
Abusive or harassing comments
Comments responding to verification that are unrelated to verification.
Requests for personal favors from the OP (For example, "OP, can you send me a signed autograph").
In AMA posts only, top-level comments must ask a question. This includes "OMG I love you..." and "No questions, just thanks!"
Comments where there would be no possibility of a real answer, especially where it is deliberately creepy or offensive.
"I bet OP won't answer this"-type responses, which usually come after the OP has finished responding to questions.
"Fluff," non-contributing responses from users, responding to all of the OP's comments for karma/attention.
Repeatedly asking the same question, which violates Reddit's site-wide rules.
Users attempting to bypass the rules by adding a ? to a non question will be permanently banned from the subreddit.
A subreddit or other website organizing and voting for a group comment/question is considered to be vote cheating and is subject to removal. It is a violation of the rules of reddit and risks a sitewide ban.
Questions must be directed toward the individual(s) doing the IAMA.
Under our policies, astroturfing is the practice of an individual or group of individuals who plant questions in an IAmA post for a particular purpose. Behavior of this kind will result in a permanent ban from /r/IAmA.