I have tried very hard to comply with the spirit of this forum but obviously still have not got the hang of it. I write a short comment and then am told it should be an answer.
I answer a question and it is down voted but no reason is given. Here is an example https://physics.stackexchange.com/a/307799/104696 which obviously flummoxed another contributor, @sammygerbil, to this forum. If nothing else I think that this is inconsiderate and possibly rude. It also does not help me to try and do better in the future.
However I wish to have guidance about this question and my answer. Having recently been told not to write answers as comments I wrote it as an answer. The reason why I wrote an answer is because I thought that I would be helping this student about a physics concept. In this case it is the idea of a non-uniform acceleration where the student thinks that one formula fits all situations. At the start of learning physics many students find this conceptually difficult.
I did not give an answer or any working I just told him/her how acceleration is defined. After writing the answer and before doing some gardening this afternoon I had an idea that there may be a contrary view when "-1" turned up but without a comment what was I supposed to do? I have absolutely no objection to the forum being overseen but I do wish to be helped to do the right thing and a comment with regard to a down vote would help a lot.