I've had comments deleted before due to the be nice policy. Won't argue against that - if it's the rules, it's the rules.
However, a few hours ago I posted a comment which I believe did not violate be nice and it got deleted.
It was in this question: Mobile Hydroponics Vehicle
I like the question and I am trying to be helpful. I did an edit to fix formatting and left my vote. I also did a comment which has been deleted. As I recall, these were the exact words, which start by quoting a piece of the question:
"Farmland needed to sustain one person ≈ 5 hectares" - where did you get this quote from? Just curious.
When I came to the question later, the comment was not there. I didn't see any "comments are not for extended discussion" notice. I also did not see any room for this question in the chat.
I have been told time and again that I may come across as offensive. I am curious whether this was the impression with the comment above (I would not be surprised). I just need to know so that I can adjust my manners to what is expected. If it wasn't a case of someone feeling offended, I would like to know what other mistake I may have done.
P.s.: in any case, I made another comment along the same lines, trying to be more polite now.