What red flags suggest bad or unsafe advice in comments?

Bad advice on Reddit often has recognizable signatures that become easier to spot with practice. The first red flag is extreme confidence about highly specific individual situations without requesting any additional information. A commenter who reads three sentences about someone's medical symptoms and immediately declares a diagnosis, without acknowledging that they have no access to the patient's history, test results, or physical presentation, is overstepping in ways that signal either naivety about how diagnosis works or a willingness to perform expertise they do not have. Advice that is actionable but irreversible without flagging the irreversibility is another red flag. Telling someone to "just file the lawsuit" or "stop taking that medication" without noting that both actions have significant and difficult-to-undo consequences reflects a failure to think about risk. Legitimate professional advice — even informal professional advice — typically structures high-stakes recommendations around what can and cannot be undone. Advice that conflicts with the consensus of relevant professional communities deserves extra scrutiny. If the medical consensus on a treatment is X and a Reddit commenter advocates for Y without being able to explain why the entire professional community is wrong, skepticism is warranted. This does not mean professional consensus is infallible, but extraordinary claims require extraordinary evidence, and "I read about this" does not meet that threshold. Comments that escalate the emotional register of a situation — "your landlord is committing a crime and you should sue immediately" when the situation is ambiguous and jurisdictionally variable — often reflect the commenter's desire to be helpful and validating rather than accurate. Advice calibrated to tell someone what they want to hear rather than what is likely to be true is emotionally satisfying and potentially harmful in equal measure.