Why don't we answer the question? Why do we drift off?
I observe that, all too often, we (me too) don't answer the question. Instead we drift off into discussions about whether the asker or one of the answerers has used exactly the right word and if not what he/she should have said. Amazingly, this occurs even when the question refers to material outside the questioner's control.
Obviously I except roundabout answers that tell a parable or a story around the question; I have to excuse those as I do it all the time.
4 Answers
If I have a sense or feeling or, heaven forbid, absolute knowledge that questions or answers are wrong, equivocal or misleading, I "drift off" if by that you mean stray from a concise and direct reply or comment.
Let me give you three examples from today's forum.
"oye como va". The question title and question body differ from each other. The question had been asked before. There was conflict in the replies. My answer is supportive of only one of the conflicting replies. I was a little loquacious. However, I thought it best to defend my position with supporting material and explanations.
" 'Sea Lion' in Spanish". There were two answers. Both of them correct. It was necessary, at least in my mind, to state that both answers are correct.
"How to say 'credited' in Spanish". I had a sense or feeling that the word sought, i.e. 'credited', was not the appropriate word for the job. While I could have answered exactly what was asked, I chose to suggest an alternative word in English and the result is a different word in Spanish than the one that was asked for.
Sometimes, it's necessary to play the role of sheepdog and to bring things back into the fold, so to speak. Sometimes a question or reply is not clear. Sometimes a respomder has clearly misunderstood the question and given an answer from left field when something closer to home base was appropriate.
There are many reasons why answers might seem to "drift off". We can only hope that such departures are warranted.
By the way, GeofC, I liked your reply to "Calíope" because you explained how others could do what you did to get to the answer thamselves. That kind of information helps both the questioner and any other member who may see and follow up on your reply.
Oh dear. I'm headed for the same practice as IZanoni, too wordy. Shut me up.
Muchos saludos/Best regards,
Moe.
I may beat around the bush a bit, but eventually (I hope) I answer the question. 
I think we do, however, it is true that this question has been asked before, so it seems we do drift off sometimes.
I have defended this position though. On other sites answers which are not strictly to the point are deleted. I have always thought that was not userfriendly. I still think so.
Drifting off and giving other examples, can help a lot to understand. After all this is a learning site, not just a "question and answer" business.
Questions about language (unlike those about, say, mathematics) often do not have a "right" / "simple" / "best" answer. Even when the questioner provides adequate context (a rare event, indeed), there can be differences of register, choices between "grammatically approved" and "what everybody says", what teenagers might say versus what their parents (or grandparents) might say, what is said in one region versus another region (or country). There are also many questions that seem to suggest that the questioner is profoundly ignorant of his "native" language" (so as to make it hard to know "what" is being asked or under some serious misapprehension about the target language (usually when the question takes the form "Should I say X or Y?" [and both are incorrect]).
In many (if not most) cases) a word or a sentence can be translated in a variety of ways (even If we are agreed on the region, register, etc.). So, when someone asks, "How do you say X in Spanish/English?" Do you provide a translation or all of the possibilities that occur to you at the moment? If someone else disagrees with your choice(s), should that person simply offer a different list of translations (or, perhaps) deviate from the central question in order to say something about the ramifications of the choices.
If someone supplies an incorrect (or overly "narrow") answer to a question, should others simply supply a "better" answer (focusing on the original poster) or should they "digress" in order to address the apparent misunderstanding of the earlier responder.
