I believe a certain amount of complaining is justifiable. I believe people run into unnecessary roadblocks on a normal, day-to-day, basis and it's always irritating to me, so I'm sure it is for others as well. I believe often the first step in changing something is complaining about it, which can lead to a more useful conversation.
Yes, I believe complaining is often justified. I think complaining serves a distinct purpose. Doctor's offices, big box electronics stores, politicians offices, newspapers - just about every one of us has had a problem with one of these at some time in our lives. Chances are we were irate over either poor service or an appliance that did not work, and addressed the issue by complaining. If we had not complained, the issue would likely not have been resolved.
Complaining that goes on and on about the same set of issues is not productive because you need to do something about what you are complaining about and then let it go or it affects you and everyone else around you negatively. But there is nothing wrong with having a friend to vent to when things really go wrong. It releases negative energy.
Complaining is justifiable but only if the complaints are followed up by some offering of a solution to the problem. Sometimes it takes more than one person with the same complaint to make an issue out of it big enough to notice and make a change. In our own homes a complaint we have in our head can be easily addressed because as the leader of the home responsibility is owned and anything done to fix the complaint doesn't have to go through a chain of people for resolution. However, at our jobs or in a restaurant or anywhere with customer service if a patron has an issue it is first noted by a verbal and or written complaint. Its taken to someone who can either resolve or get the problem directed to the right person. Its these complaints that make running a business more efficient, to the standard of the customer or employee. Simply complaining and whining and making an issue of things that are trivial or someone who complains and does not take the advice or follow through with a change, that is not acceptable or justifiable.
Yes, I believe that complaining is justifiable, because it makes us feel better about our situation. Complaining is okay because without complaining, things can never be made better. When someone complains, they are usually just blowing off steam, but sometimes raising an issue can lead to real change in the world.
While reporting issues (calmly and without accusation) can be productive, and offering solutions leads to innovation, this isn't complaining. Complaining is a time-consuming, self-pitying focus on negativity and insistently forcing that on someone else. Talking with a trusted friend can be therapeutic, and can oftentimes resolve unjustified anger and put things in perspective. In contrast, complaining is one-sided, stubborn, and doesn't necessarily invite resolution, leaning precariously close to being juvenile.