As a nuclear power plant worker I am used to following rules. Some are absolute--never to be violated even under the most extreme situations. Others can be broken, but only if the rules for breaking them are followed. And then, there are 'rules' that should really be classified as suggestions. Some writers believe in the absolute rule of "Never, ever, read the comments". Some, believe it's okay to read them but apply the second rule: "Never reply to a comment". My personal rules regarding comments are not quite so absolute.
What most writers fear are the internet trolls who, for one reason or another, seem to enjoy online bullying. Why people do this is beyond me, but have no doubt, these people are real. Check out this article by author Dougie Brimson - it will open your eyes. The best tactic against the trolls is to simply ignore them.
I have gotten negative reviews on my books. Before I uploaded my first book to Amazon back in 2009, I knew there would be people out there who would not like my writing. That's fine. I also realize there are people who love to cut other people down. If I pick up a book and after 4 chapters I quit reading it because I'm not into the author's style, I don't immediately drop a negative comment. I'm smart enough to realize that not everyone has the same tastes. I don't like lobster but that doesn't mean that if I see you eating it I'm going to think less of you. Our differences are what makes us human--it's what differentiates us from robots.
I also realize that my fans can be a goldmine of information to help make my books better. That's why I read every comment, every review, and every email. I'm looking for constructive feedback--stuff I can use and act upon to provide my fans with material they will continue to enjoy. Nobody is perfect and even the best can become better.
I follow a similar rule regarding replying to comments and reviews. If someone writes a particularly good review, I thank them. If they provide a helpful comment or ask a pertinent question, I will also reply. I never try to start an argument with anyone when I reply. Bear in mind that anyone on the planet can read what you've written. Be professional.
Two stories I would like to share. There was an individual from Australia who wrote a rather bad review of one of my books. I could sense his frustration and I felt I could gain some useful feedback but the post did not provide any details as to what the reader was upset about. I replied. I kept the reply professional and I asked for particulars. He replied and that started a private email conversation that ended up with him retracting his original post and writing a better review. We corresponded for a few months after that. It was a good experience all around. There was one individual, however, who seemed offended by what had happened. This brings me to the other story.
There was an individual who wrote a very negative review of Translight specifically because I mentioned global warming and the government was not presented as a champion of advancement. The review said nothing about the quality of the book itself. I wrote a reply which caused her to fire off an argumentative response. I nipped it in the bud by not taking the bait and simply ignored it. But, realizing that there are some out there who take offense at some things, I revised Translight slightly to tone down the discussion on climate change. I prefer to remain neutral on some matters.
My suggestion to new writers: read the reviews because without them you have no way of knowing what your fans think of your work. Read them with the intent of learning how to become a better writer. Never reply to a negative review! Doing so is what the troll that wrote it wants--you will regret it. If you to find a comment worthy of a reply, do so in a professional manner. Expect to be baited and never fall into that trap.
Writers are public figures. Be professional at all times and listen to your readers.