I usually try to read all the details before answering a question. But sometimes I don’t, either because the details are written in a rambling way that discourages me from continuing, or because they appear to be complete within the first sentence or two, and I anticipate repetition and redundancy. I’m not often sorry that I didn’t continue.
And, like @Earthbound_Misfit, sometimes I avoid reading answers if I want to give my answer without being influenced by others’ answers. Frequently, however, I do read all the answers.
And sometimes, I half-read the details, decide it’s not worth answering, then I read all the responses, and am stirred to respond to something someone other than the OP said. Some people seem to dislike this, but that’s how I Fluther, and I see others do it as well.
We all come to Fluther for different reasons, and we all have our interest captured by different kinds of things. It takes a certain spark to lead one to leave a comment – that’s not always going to come from the recipe of (1) Read the question. (2) Read the details thoroughly. (3) Read all the responses. That’s the risk you take when you leave a question on a public forum. You have to relinquish your ownership of the question – other people are going to respond as they wish.
And, as @Earthbound_Misfit also mentioned, sometimes the OP states a question + details in a way that appears perfectly clear to themselves, and yet is full of ambiguities for the readers to interpret in their own ways. I’ve seen this happen an awful lot here, and seeing the OP come back and complain indignantly is, well, kind of funny and kind of sad. The asker has to be able to let these things go.