Don't worry about your English. The downvote was probably because of the "It is nonsense", which is slightly harsher than convention here is willing to tolerate (rightly so, IMO, lest threads turn into shouting matches). Please don't comment about being downvoted. It goes against http://ycombinator.com/newsguidelines.html and earns an automatic downvote from many of us. Also, downvoting to express disagreement is common on HN, because one may disagree without having the time and/or anything substantive that is worth posting a comment to say.
"Also, downvoting to express disagreement is common on HN, because one may disagree without having the time and/or anything substantive that is worth posting a comment to say."
Really? I don't think that's its purpose though. I think it's meant to be used for comments that detract from the discussion or otherwise don't follow guidelines. Downvoting because you disagree just leads to a form of groupthink (imho).
Case in point: I'd disagree with the quoted comment above but I'm certainly not going to downvote your post because of it.
I don't think it's the most common case. Most common is when you find something obnoxious about a post. But it's common enough and (as pg has said several times) legitimate enough that the people (not you!) who indignantly protest "That's not what downvoting is FOR!!" really have no basis for doing so.
A certain amount of groupthink is probably inevitable in a community, but is there evidence of it being a big problem here? For example, are there many (any?) heavily downvoted comments that don't fairly obviously deserve it? People call "groupthink" sometimes when they don't want to see how they were being rude.
A far worse problem in my view is the huge area under the curve at the tepid mean. It's hard to downvote a comment just for being bland and pointless. It would be nice if HN could solve the problem God solves in the Book of Revelation: "So then because thou art lukewarm, and neither cold nor hot, I will spew thee out of my mouth."
