Yesterday I have 287 answers in my profile, today 284. I don't know which answers disappeared, the only thing I can say is that I lost some reputation in functional analysis tag. What has happened? I often put a lot of efforts in my answers, so I don't want them to be deleted without my permission.
An account was deleted. This deletes questions with a negative vote total, so deletes the corresponding answers.
For future reference, here is a relevant section of the terms of service (emphasis added):
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I agree Henning Makholm that if a question got an answer with a positive score, it will stay on the website independently of the score of the question. It's not for the reputation points,
even if I lost a lot of points, as it's just an arbitrary quantity.
The major problem is that for example we provide a long answer, or we spent a lot of time to think on it or type it, and there will be no trace of it. A good thing would be to upvote the question, but sometimes we can forget, or don't give the upvote because there was something unclear in the question (and in this case we wait for a clarification, but it may never come, or latter but we don't see it).